Amsonia ‘Blue Ice’
Blue Ice Eastern Bluestar
****
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Flower description / bloom time
Dark blue buds open to clusters of bright, lavender-blue, star-like flowers from May into June for about 6 weeks. Each star-like bloom is ¾ inch wide.
Foliage interest—color/texture
‘Blue Ice’ has very clean, lustrous green, willow-like foliage that turns yellow in fall.
Habit and growth rate observations
This is a compact, mounded plant. The size reported varied from 1 to 2 feet tall but the width averaged twice as wide as tall. This compact cultivar does not need to be cut back after flowering, and generally requires no staking or support when grown in full sun to part shade.
Site preference—soil and light
‘Blue Ice’ does well in sun to light shade. It performs well in average garden soil with good drainage. The trial for Amsonia ‘Blue Ice’ included the drought of 2005 and it performed very well with only a little extra watering required.
Successes and possible drawbacks—how to overcome them
The strong habit and easy care make it a great choice for the garden. It lacks the size of Amsonia tabernaemontana and the fine-texture of Amsonia hubrichtii but makes up for it with darker, more impressive flowers and a sturdy mounded habit.
Notes from growers/retailers
Although it is a slow grower with a long production time [slow to fill a #1 container], it has no pest or disease problems. Amsonia ‘Blue Ice’ is rated USDA Zones 4 to 9 for hardiness.
Best combinations
‘Blue Ice’ can be combined with taller grasses such as Calamagrostis x acutiflora ‘Stricta’ (feather reed grass), Iris sibirica ‘Caesar’s Brother’ which bloom at the same time, and contrasts nicely with Heuchera ‘Lime Rickey’ or other plants with yellow or chartreuse foliage.
Parting SHOT — the overall evaluation results were Excellent ****
All plants under evaluation survived in each location. Amsonia ‘Blue Ice’ was rated as an excellent plant for the garden for its great blooms, pleasing foliage and clean form. It is a carefree plant requiring no extra care but adds beauty to the garden with its spring flowers, summer foliage and habit, and added yellow fall color.
Evaluated 2004-2007
Astilbe X arendsii
‘Beauty of Ernest’
Color Flash® Astilbe
*
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Flower description / bloom time
This Astilbe has airy plumes of fragrant, pale pink. The flowers are supposed to bloom June through August; however, one evaluator noted its bloom time as being only in August and some evaluators noted it did not flower at all. It was observed that Color Flash® was not as floriferous as Astilbe ‘Hennie Graafland’.
Foliage interest—color/texture
Compound leaves emerge a rich green, turning slightly glossy, lower leaves edged with burgundy or red as the season progresses.
Habit and growth rate observations
The foliage becomes a vigorous mound to 12 inches tall and 24 inches wide. The blooms add 12-18 inches of height in mid-summer.
Site preference—soil and light
This plant grows best in part sun or dappled shade. It prefers constant moisture and will need supplemental watering in extreme heat.
Successes and possible drawbacks—how to overcome them
This Astilbe’s strong growth and changing foliage color keep this plant interesting throughout the season. It can have leaves in all shades of green and burgundy to red at the same time. The flowers attract butterflies and it does not appear to attract deer or rabbits. It was recommended by evaluators that Color Flash® be deadheaded so that the color on the foliage stands out. Keep this plant well watered since it needs moist soil for best performance; a mulch will help to retain the soil moisture. It was not bothered by slugs or other insects or by rabbits.
Notes from growers/retailers
This plant looks great in a container and the colored foliage stands out on a retail bench. Although easily grown, it is patented so propagation is by license only.
Best combinations
Color Flash® works well in combination with ferns, especially Dryopteris filix-mas and Ajuga ‘Black Scallop’.
Parting SHOT— the overall evaluation results were Poor *
This one was hard to rate, because there is nothing wrong with it, yet there is nothing outstanding either. It certainly has nice clean foliage and grows well.
Unfortunately, Color Flash® demonstrated weak growth for most of the evaluators. Three of the evaluators lost the plant completely and only two had 100 percent survival during the testing period.
Evaluated 2005-2008
Aster tataricus ‘Jindai’
Jindai Tatarian Aster

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Flower description / bloom time
Small, ¾-inch, lavender-blue daisies with a yellow center are clustered at the tips of the stems. ‘Jindai’ blooms in September and October.
Foliage interest—color/texture
Distinctive paddle-shaped, almost tobacco-like basal leaves are up to 18 inches long and 5 inches wide. Leaves on the upper stems are smaller.
Habit and growth rate observations
‘Jindai’ is a compact plant with upright stems to 4 or 5 feet tall, which is about 2 feet shorter than the species. It spreads by rhizomes to 3 feet wide.
Site preference—soil and light
Tatarian aster is easily grown in average, well-drained soils in full sun.
Successes and possible drawbacks—how to overcome them
‘Jindai’ features late-season lavender-blue flowers and a different habit from most commonly grown asters. Divide Jindai every 3-4 years if needed to control growth. Plants can spread widely by rhizomes under optimum growing conditions. This is the only aster that rabbits do not eat!
Notes from growers/retailers
‘Jindai’ had no grower notes except that it was long-lived and trouble free.
Best combinations
Calamagrostis acutiflora ‘Karl Foerster’ and Eupatorium maculatum are good companion plants for ‘Jindai’.
Parting SHOT— the overall evaluation results were Good
Bold and colorful best describes this showstopper! Pretty late season lavender-blue flowers, bold foliage, and an upright habit give ‘Jindai’ a nice presence in the garden. It’s habit can be aggressive, so a word of warning to gardeners is warranted. ‘Jindai’ is a great aster for massing or for the back of the perennial border.
Evaluated 2004-2007
Athyrium ‘Ghost’
Hybrid Fern
***
Flower description / bloom time
Ferns are non-flowering plants.
Foliage interest—color and texture
Ghost fern with its soft silvery gray fronds and dark maroon midrib is a cross between Athyrium nipponicum var. pictum (Japanese painted fern) and Athyrium filix-femina (lady fern). It exhibits the silver coloration of Japanese painted fern and the upright character from its lady fern parentage. The fronds of the Ghost fern start out silvery in the spring, and age to a grayish green as the season progresses.
Habit and growth rate observations
The plants have a mature height of 24 to 30 inches and a spread of 18 to 24 inches. It is this fern’s more upright habit that makes it different in the Japanese painted fern world.
Site preference: soil / light
Ghost fern does best in partial shade with moist, rich, loamy soil but is tolerant of full shade.
Successes and possible drawbacks—how to overcome them
This deciduous fern was rated Good by the perennial evaluators for habit, foliage and overall effect. Although the Ghost fern was introduced as an improvement over Japanese painted fern, the evaluators didn’t necessarily see this as better, but its habit and leaf color does provide a slightly different feel in the garden.
Notes from growers / retailers
There were varying reports from growers: Two and one half inch plugs finish in 8 to 10 weeks which are then potted in June for sale the following year. Another grower uses a four and one-half inch plant as a liner in order to get a full plant. And yet another grower reported inconsistent vigor for this fern being slow to fill a one-gallon container.
Best combinations
Brunnera macrophylla, Heuchera ‘Plum Pudding’, Viola labradorica, Carex morrowii ‘Ice Dance’
Parting SHOT —the overall evaluation results were Good ***
Athyrium ‘Ghost’ overall received a Good rating from evaluators. Despite not being so different from other Japanese painted ferns, one evaluator suggests that Ghost fern still has a place in the shade garden. Any plant that brings color into the shade garden has value! But most of the Evaluation Team said they would not recommend this fern over Athyrium nipponicum var. pictum.
Evaluated 2002-2005
Baptisia x variicolor ‘Twilite’ PPAF
Twilite Prairie Blues False Indigo
***
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Flower description / bloom time
Slow to establish flowers are often hidden in foliage or may not flower in year one. Once set, dark chocolate/ purple flowers highlighted by lemon yellow tips on tall stems up to 32″ above the foliage create a striking floral effect. Flowers fade to violet-purple. Blooms approx. three weeks from late May into June. Good cutting flower attracts many types of butterflies.
Foliage interest – color/texture
Clean, blue- green to blue- grey foliage. In partial shade foliage will present overall green. Seed pods create winter interest
Habit and growth rate observations
Nice, clean shrub-like habit exhibits slow growth the first year. Grows 3’ tall by 3’ wide when mature and may create an overall rounded form.
Site preference – soil & light
Evaluation sites ranged from full sun to part shade and evaluator’s noted plants became floppy on shadier sites. Twilite was successful on sites ranging from well drained soil to heavy clay.
Successes and possible drawbacks – how to overcome them
Cut back to the ground in the spring. Some plants attracted Japanese Beetles in 2010 but damage was not enough to disfigure. Cage in early spring if preference is for upright plant.
Notes from growers/retailers
Excellent grower with low maintenance requirements. Finishes on the small side in one season so it may be difficult to find full pots on the retail table
Best combinations
Coreopsis Golden Showers, Geranium sanguinium, Stokesia Mary Gregory, Sedum Neon, Iris hybrids, and ornamental grasses. Use Nepeta at the base to layer in the garden.
Parting SHOT – Overall evaluation results were Good/3.5.
Recommended for the texture and seasonal interest in the garden. Twilite’s large habit creates an excellent backdrop for the deeper perennial border or as a structural accent. Standout glowing purple flower color is attractive to butterflies.
Evaluated 2007-2010
Bergenia ciliata
Hairy Bergenia, Pigsqueak
***
Flower description / bloom timePanicles of pink buds open to a one-inch blush pink flower above emerging foliage. As flowers mature they turn rose pink.
Foliage interest – color/texture
Flowers bloom in early spring as foliage is just emerging. By June foliage has matured and is the best feature of the plant. Leaves can be 6-8 inches in diameter and are reminiscent of African Violets. Dark green, hairy foliage remains lovely all summer and gives great texture to the garden border. In the fall the foliage declines and remains green.
Habit and growth rate observations
Bergenia ciliata forms a mounded clump 8 inches tall and ranging in spread from 12-20 inches wide; not fast growing. Correct siting is very important for the foliage to look its best; avoid dry or excessively moist locations.
Site preference – soil & light
Bergenia ciliata likes part sun to shade and average to moist soils and will tolerate clay soils.
Successes and possible drawbacks – how to overcome them
Flowers aren’t reliable from year to year depending on cold and late freezes that may inhibit bloom in early spring. Best success will be in light shade on a moist site where it is not allowed to dry out; yet not overly wet. Can attract deer or rabbit browsing although listed as being critter resistant. Foliage was stunted in growth during years when there was excessive moisture or drought. Placed in too much sun foliage will rust out in summer.
Good combinations
Astilbe, Hosta, Ajuga ‘Chocolate Chip’, Cimicifuga, Aruncus aethusifolius or Aruncus dioicus
Parting SHOT – the overall evaluation results were Good
Foliage is the highlight of this plant and its quality texture performs when well-sited. Fuzzy oversized leaves are interesting all summer. The early spring flower, although not dependable, is attractive when it appears. Siting is very important for the success of this plant.
Evaluated 2007-2010
Brunnera macrophylla ‘Jack Frost’
Siberian Bugloss
****
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Flower description / bloom time
Jack Frost has China-blue sprays of flowers in April and May for 3 to 4 weeks with no repeat flowering later in the season. However, flowers are not Jack Frost’s main featuer— flowers only received a ‘good’ rating over the evaluation period.
Foliage interest / color and texture
Medium green, heart-shaped leaves are heavily marbled in silver-white. The variegated foliage boldly stands out as a ‘color’ throughout the growing season in the shaded garden. Even in a drought year [2005] foliage did not have browned edges.
Habit and growth rate observations
The mounded habit of the foliage takes about a year from planting to achieve a height of 12 inches with the flowers adding an additional 9 inches. The plants reached a width of 18 to 24 inches in a 2- to 3-year period.
Site preference / soil and light
Jack Frost grows best in slightly moist, well draining soil in part shade or shade. It showed great drought tolerance in 2005 while growing under Norway maples.
Successes and possible drawbacks—how to overcome them
Showy foliar variegation stands out in shaded gardens from April to November. For appearance the plant looks best if the spent flower stems are removed. It was also thought that seedlings might revert to the species but on at least one site the seedlings remained true to type. There was only one report of minor slug damage.
Notes from growers / retailers
Foliage seems to be very consistent and nicer than other variegated Brunnera macrophylla cultivars. As recommended for garden planting, Jack Frost requires excellent drainage to avoid root diseases. By mid-June the plant develops nice foliage, is moderately rooted and in bloom. Jack Frost can be potted bare root in mid-April and grown outdoors under 30% shade cloth. One grower generally sells about 75% and over winters the remaining 25% under micro foam and white plastic right on the ground. Another grower recommended growing plants in a ‘squat pot’ (wider than tall). Brunnera is also salt-sensitive so growers should periodically drench soils to remove excess salt.
Best combinations
Some suggested companion plants include Athyrium filix-femina ‘Frizelliae’, Carex ‘Ice Dance’, and Impatiens ‘Lipstick’.
Parting SHOT —the overall evaluation results were Excellent ****
Brunnera macrophylla ‘Jack Frost’ is an easy-care perennial for brightening a darker area of the garden – it is the foliage of Jack Frost that makes this plant a standout! For most of the evaluators this plant performed well in dry, shaded conditions filling a much-needed position in the garden. Jack Frost received the highest overall rating of Excellent ****.
Evaluated 2002-2005
Brunnera macrophylla ‘Looking Glass’
Looking Glass Siberian Bugloss
**
Flower description / bloom timeLight blue forget-me-not-like flowers with yellow centers appear in early April and lasted four weeks for some of our evaluators. Others noted plants never bloomed or bloomed sporadically.
Foliage interest – color/texture
Unique feature of this medium textured plant is the silver heart-shaped foliage with fine green veins.
Habit and growth rate observations
On sites where Looking Glass performed best, mounds were 12 inches tall and 18 inches wide, with flowers floating 6 inches above the basal foliage. Plants that struggled and bloomed sparsely or not at all were 10 inches tall and 8 inches wide.
Site preference – soil & light
Plants did best in dry shade with some morning sun. Good soil drainage is essential.
Successes and possible drawbacks – how to overcome them
Plant Looking Glass with good air circulation and water only as needed in the morning hours. Looking Glass competed well with maple roots, but two hours of exposure to high sun caused leaf edges to scorch. Some evaluators found that a top dressing of compost in spring and fall was beneficial. In all but one site, the foliage was affected by black leaf spot during the hot and humid days of summer.
Notes from growers/retailers
Looking Glass looks good in a container but has a short retail shelf life. Grow Looking Glass on the dry side and monitor salts carefully. Keep fertilization low. Does not like heat and growth rate is slow.
Best combinations
Actaea racemosa, Peonies, Carex pensylvanica, Narcissus, Aster divaricata (Eurybia divaricata), Ferns and Hosta
Parting SHOT – the overall evaluation results were Fair**
Even though the mostly silver leaves are very striking, the overall plant performance is not as dependable as Brunnera macrophylla ‘Jack Frost’ or Brunnera macrophylla.
Evaluated 2007-2010
Calamintha nepeta ssp. nepeta
Calamint
**
Flower description / bloom time
Calamintha has masses of dainty white flowers that change to soft blue as they age. The tiny blooms dance airily just above the foliage continuously from June through October!
Foliage interest / color and texture
Calamintha is a fine-textured plant with rich, shiny green foliage. A member of the mint family, the leaves have a peppermint fragrance when crushed.
Habit and growth rate observations
This upright plant is approximately 12 to 18 inches tall and wide. It forms a clump and is not spreading or aggressive.
Site preference—soil / light
Calamintha grows in full sun with ordinary soils and requires little care. Be careful not to cover the crown of the plant when planting. Heavy mulch and over-irrigating is not necessary and can, in fact, be detrimental. Less tender, loving care is better for calamint.
Successes and possible drawbacks—how to overcome them
Be sure to get the subspecies since the straight species Calamintha nepeta will reseed and has dull gray-green leaves. The more desirable Calamintha nepeta ssp. nepeta has small glossy leaves and is sterile.
Notes from growers / retailers
The true plant is supposed to be sterile or semi sterile. From cuttings, it takes three months to have ready for sale. Two and one-half inch plugs finish in 5 to 6 weeks, bloom in late July. Calamint makes a great plant for August sales and over winters easily under micro foam and white plastic.
Best combinations
The Evaluation Team rated this plant Fair in most categories but recommended its use overall as a long blooming perennial to use as a filler among ornamental grasses, roses or perennials.
Parting SHOT —the overall evaluation results were Fair **
While not overly impressive by itself, it really shines as a filler plant or a plant to weave in and around plants, especially in the rock garden.
Evaluated 2002-2005
Campanula glomerata ‘Freya’
Freya Clustered Bellflower
**
Campanula ‘Freya’ is a clustered bellflower touted for use in front-to-middle of a border, in foundation plantings, mass plantings, butterfly gardens, cutting gardens and cottage gardens.Flower Description and Bloom Time
Star-shaped clusters of deep violet/purple flowers bloomed from June into July.
Foliage Interest — Color and Texture
Coarse, green foliage stayed healthy until later in the growing season when it turned brown and yellow in some evaluation sites.
Habit and Growth Rate Observations
Plants ranged in size from 13 to 18 inches tall and 10 to 12 inches wide. While some plants remained sturdy, others flopped and grew slowly throughout the season.
Site Preference — Soil and Light
Prefers full sun and moist, well-drained soil.
Successes and Possible Drawbacks
When in flower, the plant wowed evaluators with its deep purple flower clusters. After blooming, the foliage browned and turned yellow on some plants. To clean up the plant after blooming, evaluators recommended removing all the stems down to the basal foliage, the leaves closest to the ground and crown of the plant.
Notes from Growers/Retailers
N/A
Good Combinations
If you try this plant, pair it with other sun-loving perennials such as Coreopsis, Echinacea, Liatris and Stachys.
Parting SHOT — The overall evaluation results were poor. **
Three evaluators trialed this plant from 2012 to 2015 in the western suburbs of Chicago and in northern Illinois near the Wisconsin border. Although the plant is rated for Zones 3 to 8, most of the nine trial plants were dead by the third year. Problems with lack of flowers or foliage that was unsatisfactory accounted for the low ratings.
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Campanula ‘Samantha’
Samantha Dwarf Hybrid Bellflower
***
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Flower description / bloom time
Pretty, dainty, long blooming, fragrant, upward facing, ¾ inch violet-blue flowers with a white halo inside. Samantha blooms constantly [almost ridiculously], starting in June through summer with a little maintenance.
Foliage interest—color/texture
This bellflower forms a mat-like mound of dense, deep green heart-shaped foliage and is fine textured. No disease or insect problems were noted.
Habit and growth rate observations
The slow spreading mat forms a dense mound and remains compact in ideal conditions. If exposed to excess moisture or too much shade, it can sprawl to 20 inches and open in the center.
Site preferenc—soil and light
Samantha prefers full sun to light shade and is easily grown in moist well-drained soils. Heavier shade leads to fewer flowers and a sprawling open habit.
Successes and possible drawbacks—how to overcome them
Exceptional blooming characteristics and dense foliage make Campanula ‘Samantha’ an excellent choice for the edge of the border, rock garden or mass planting. Although deadheading is time-consuming due to the amount of flowers, it will significantly improve the appearance of these bellflowers. Deadheading or shearing after the initial heavy bloom also encourages plants to push more flowers and extend the bloom period.
Notes from growers/retailers
This bellflower is a good retail seller because it grows easily, begins blooming in early summer, and has neat and tidy foliage.
Best combinations
Samantha works best as an edger in the garden and mixes well with all other colors.
Parting SHOT —the overall evaluation results were Good ***
The profuse and repeating bloom of blue, up-facing flowers makes Campanula ‘Samantha’ very desirable. But in years with heavy spring rains the stems did ‘lodge’ or fall away from the center.
Evaluated 2004-2007
Campanula ‘Sarastro’
Bellflower
*
Flower description / bloom time
Large, 2 ½ inches long, dark purple, bell-shaped flowers appear heavily in June for about two weeks, and then smaller flowers appear sporadically through August.
Foliage interest / color and texture
Small heart-shaped leaves are medium green and a medium texture, which stay healthy all year long.
Habit and growth rate observations
Sarastro is a cross between Campanula punctata and Campanula trachelium and is 18 to 20 inches tall with an equal spread. The growth rate is slow and by underground rhizomes.
Site preference / soil and light
The most successful plantings were in moist, well-drained soils with supplemental watering and a light mulch. These received morning sun and afternoon shade. Some plants sited in full sun died the first year.
Successes and possible drawbacks—how to overcome them
The positives reported for Sarastro were the showiness of the flower and stems that remained more up right than Campanula ‘Kent Belle’. Cutting the plant back after first bloom rarely resulted in a good second flush of growth.
Notes from growers / retailers
While easy to grow in pots, the plant does not have much eye appeal in containers, unless it is in bloom.
Best combinations
The dark purple flower color will combine nicely with soft pastel colors such as pink, lemon yellow, and white. Some suggestions included Achillea ‘Moonshine’, Iris sibirica ‘Gull’s Wing’, Geranium sanguineum ‘Album’, and Geranium ‘Ankum’s Pride’.
Parting SHOT —the overall evaluation results were Fair to Poor *
The Evaluation Team did not recommend this plant, as the overall rating was Fair to Poor. The showy flower display in June was rated good to excellent, but problems with vigor and hardiness brought the ratings down. In our study, only 65% survived the three years. It did stay more upright than Campanula ‘Kent Belle’, but still needed some support during its heavy bloom period.
Evaluated 2003-2006
Carex dolichostachya ‘Gold Fountains’
Carex dolichostachya Gold Fountains™ ‘Kaga-nishiki’
*
Gold Fountain ‘Kaga-nishiki’ is a dense, clump-forming sedge with fine-textured
yellowish leaves, Grown primarily for its foliage and arching form, it is touted as a
ground cover for the shade garden.
Flower Description and Bloom Time
Like most Carex flowers, they are small and unremarkable when they appear in spring.
Foliage Interest – Color and Texture
The narrow, fine-textured leaves have a cream-chartreuse edge and form an arching
mound.
Habit and Growth Rate Observations
The plant forms an arching mound that is very slow growing. In the evaluation gardens,
it barely filled out to a 6-inch width over the summer. In optimal conditions, the plants
will eventually form a 2-foot wide, arching mound.
.
Site preference — Soil and Light
This plant prefers a half day of sun and well-drained, moist soil. It does not do well in
clay soils that have not been amended with organic compost or mulched leaves. Thrives
in moist soils, but will grow well in average garden soil as long as plants do not dry out.
Success and possible drawbacks
Although this plant is evergreen in Zones 7 to 9, it has little foliage color in northeastern
Illinois unless winter temperatures are unusually mild. For best growth results, cut the
plant back in late winter or very early spring.
Notes from Growers/Retailers
N/A
Good Combinations
Hostas, Iris cristata, Dennstaedtia punctilobula (hay-scented fern)
Parting “SHOT” –The overall evaluation results were Poor*
Of the 14 plants evaluated, only 3 survived. This plant is a gamble but you may be sold
on its wispy, fine-textured foliage. Otherwise, don’t expect it to survive over the duration
of several winters. Not recommended for our area.
Evaluated 2002-2005
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Carex platyphylla
Silver Sedge
*
Flower description / bloom timeThis foliage plant produces no true flower and is native from the East Coast to the Missippi.
Foliage interest – color/texture
Semi-evergreen, lanceolate leaves are 1-2 inches wide by 8-10 inches long. Showy powder blue to blue-green color. Spreads slowly in clumps to form a lovely textured groundcover.
Habit and growth rate observations
Grows slowly into clumped mound 8-12 inches high by 12-24 inches wide. Tendency to heave with freeze/thaw cycles in winter.
Site preference – soil & light
Moist, well –drained organic soil in deep to part shade. Needs moist conditions to establish; did not take dry shade in evaluator gardens.
Successes and possible drawbacks – how to overcome them
Success with this sedge depends on placement: Amended, well-drained soil, part shade with supplemental watering or irrigation system. Mulch well in fall and prune back in spring. Establishment appeared better if planted in groupings of 3 or 5. Beware: Attractive munching for dogs!
Notes from growers/retailers
After establishment, plant may take drier conditions in shade. Best performance with a hard clipping in spring.
Best combinations
Could pair well with other 12+ inch shade plants such as: Heuchera americana ‘Green Spice’ or Heuchera micrantha ‘Paris’, Brunnera macrophylla ‘Jack Frost, and ferns like Adiantum pendatum , Dryopteris marginalis, and/or Athyrium felix-femina
Parting SHOT – the overall evaluation results were Poor
Over-winter hardiness issues and slow growth rate overall make this an iffy selection. There are better native sedges to try such as: Carex ‘ Ice Dance’, Carex pennsylnvanica!
Evaluated 2005-2008
Caryopteris ‘Snow Fairy’
Snow Fairy Bluebeard
***
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Flower description / bloom time
The soft blue flowers begin blooming in late July and are ¼ inch or less in small clusters on the tip and sides of the stems. Though pretty, they can get lost in the bright, variegated foliage.
Foliage interest— color/texture
This bluebeard has fine-textured, variegated foliage. The 2-inch leaves are toothed, sage green, with an irregular white margin. The foliage is clean throughout the season and the variegation has a strong effect in the garden until frost. When crushed or bruised, foliage has a mint-like fragrance.
Habit and growth rate observations
‘Snow Fairy’ has a vase-shaped habit that reaches 24-30 inches high and wide. Though very slow to return in the spring, it shows more vigorous growth by mid-summer.
Site preference—soil and light
‘Snow Fairy’ is said to prefer sun to light shade in average, well-drained soils, but it also did well in the shady garden [see picture below]. It did not overwinter in wet soils.
Successes and possible drawbacks – how to overcome them
The bright, clean variegated foliage provides interest all season and the mid-size, graceful form of the plant makes it multifunctional in the garden. However, it emerges as late as early June, so do not be too hasty to assume it has died. Rabbit problems can require fencing for protection.
Notes from growers/retailers
Growers consider this plant to be an easy container plant to grow with an average finish time. They suggest starting small, shifting up to a larger pot size and pruning once to fatten” up the plant. Grow in part shade for best coloring of the foliage.
Best combinations
Consider combining ‘Snow Fairy’ with Stachys byzantina and Geranium sanguineum. It goes well with bright colored flowers and plants with bolder foliage.
Parting SHOT— the overall evaluation results were Good ***
This plant is no trouble at all and makes a big foliage statement from June until frost. The flowers do not show up unless you are standing close, but who cares? Foliage and growth habit make this plant a winner!
Evaluated 2006-2009
Digitalis ‘Spice Island’
Spice Island Foxglove
***
Flower description / bloom timeThe 2-inch florets of cream-yellow with light orange blush appear on 24-30-inch racemes in early June and continue mid to late June. Sporadic re-bloom in late July through mid-August occurs with or without cutting back spent flowers.
Foliage interest – color/texture
Dark green, medium textured foliage is glossier than the species and grows from a basal clump. No fall color but foliage remains somewhat evergreen in winter.
Habit and growth rate observations
Two to three flowering stems spring from the 12 inch tall by 18-24 inch wide clump. Slow growth rate results in a plant that stays in place and does not reseed. Flowers do not flop, but may grow toward sun in shadier sites.
Site preference – soil & light
Best results were reported in gardens with well- drained, clay loam soil and part shade conditions.
Successes and possible drawbacks – how to overcome them
Hummingbirds were observed feeding on the flowers. Deer and rabbit resistance is a big plus for foxgloves. Lack of vigor in our climate can be helped by providing good drainage and adding organic matter to the soil.
Notes from growers/retailers
It looks great in a #1 pot and is a quick grower for Digitalis. Grow plants on the drier side with no pruning or pinching required for fullness.
Good combinations
Combining ‘Spice Island’ with Hosta ‘Touch of Class’ and Aruncus aethusifolius highlights the yellow flower color and provides textural contrast.
Parting SHOT – the overall evaluation results were Good
The evaluations were sharply split on this foxglove—half of the comments were glowing, half the ratings were fair to poor. Plant losses were observed in all trial gardens, and were most likely due to the wet spring of 2009. The more successful plantings were appreciated for their attractive flowers and foliage over the summer, deer / rabbit resistance, and food for hummingbirds.
Evaluated 2007-2010
Echinacea ‘Art’s Pride’
Orange Meadowbrite Coneflower
**
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Flower description / bloom time
‘Art’s Pride’ features beautiful orange coneflowers, 3-4 inches across, that fade to pale pink over time. Few flowers on each plant, yet they have a sweet subtle fragrance, and make great cut flowers. It blooms from late June through early August, with intermittent flowers into early fall.
Foliage interest—color/texture
While the grass-green, lanceolate leaves of ‘Art’s Pride’ are not a significant ornamental feature, they are healthy all summer. The basal leaves are not densely produced.
Habit and growth rate observations
Due to somewhat spindly habits, plants work best when planted next to other perennials or grasses that help support the weak stems. ‘Art’s Pride’ is a slow grower, 36 inches tall and 24 inches wide after three seasons. Only 11 of 38 plants trialed survived over winter (a 29% survival rate).
Site preference—soil and light
Grows best in full sun and well-drained soils. Supplemental watering is needed, especially during establishment. Amending soil with compost is beneficial.
Successes and possible drawbacks—how to overcome them
Not a good plant when planted by itself, since it needs other plants to lean on for support. Cutting the plant back once before it blooms may encourage development of a sturdier compact habit. Orange bloom is magnificent and provides a continuous show as it fades from orange to pale pink.
Notes from growers/retailers
‘Art’s Pride’ was the first orange-flowered coneflower in the market introduced via the Chicagoland Grows® plant introduction program. The flower color is appealing to gardeners and will sell if in bloom at the garden center.
Best combinations
Combines well with a variety of perennials and grasses including Liatris, Aster, Rudbeckia, Sporobolus, Pervoskia, Sessleria, Heliopsis, Helianthus, Sedum, Pennisetum.
Parting SHOT”—the overall evaluation results were Fair ••
Stunning orange blooms are a stand out in the garden and contrast well with the yellow and purple blossoms of other perennials. ‘Art’s Pride’ needs the support of adjacent perennials or grasses to prevent it from falling over. The vigor and hardiness is questionable, as a large percentage of our trials did not overwinter very well.
Epilobium canum ssp. garrettii ‘Orange Carpet’
Orange Carpet Hummingbird Trumpet
**
Flower description / bloom timeThis plant is related to Fuchsia as is evident in the trumpet shape of the flower and the attraction of hummingbirds to the plant. Orange Carpet is covered with a mass of small orange flowers for three plus weeks in July and sporadically through September. Most evaluators reported decreased flowering in each year of the three-year cycle with more foliage than flower by the third year.
Foliage interest – color/texture
Orange Carpet is fine-textured with tiny, grey-green leaves. Foliage is pubescent with slight textural twisting of the leaves. No fall color. Plant decline over three year trial presented as a gradual decline in foliage quality. Foliage was healthy the entire first season; slight browning on the edges coincided with flowering in July of the second year, and leaves were so browned out in the third year plants were cut back.
Habit and growth rate observations
Orange Carpet is a mounding plant with arching or relaxed stems typically growing 8 to 12 inches tall by 14 to 18 inches wide. Often described as a groundcover, it can also grow more upright and resemble a small shrub. The full habit and cascading nature makes it useful over a rock wall until mid-season when the dull, brown foliage and sprawling habit takes over.
Site preference – soil & light
Native to the western United States, Orange Carpet Hummingbird Trumpet prefers average, well-drained soils in full to part sun.
Successes and possible drawbacks – how to overcome them
Hot orange color is attractive against grey-green foliage and attracts hummingbirds. Poor mid-season foliage quality and sprawling habit detracts from overall success. An early summer pruning may alleviate the floppy habit, and cutting the plant to the ground after flowering helps with the unsightly foliage.
Notes from growers/retailers
Growers reported that this is an easy plant to grow though flower production was lower than expected.
Great combinations
This plant looks especially good planted with blue-toned foliage to complement the orange flowers. It pairs well with Juniperus squamata ‘Blue Star’.
Parting SHOT – the overall evaluation results were Fair**
Some evaluators recommended it for the home garden and described it as a fun plant for a hot, dry to average spot in the garden. Others felt it was a huge disappointment and could not wait to take it out of the garden once the evaluation period was over.
Evaluated 2007-2010
Epimedium ‘Amber Queen’
Amber Queen Bishop’s Hat, Barrenwort
***
Flower description / bloom timeBright yellow spider-like flowers tipped with an orange- red cap bloom April –May. The ¼ to ½ inch flowers seem to float in space on thin, arching stems. The flowers were self cleaning and did not require deadheading. May not bloom each year based on early conditions.
Foliage interest – color/texture
Spring foliage is green mottled red and a slightly serrated edge. In summer the full heart-shaped leaves turn all green; sometimes with a yellow tinge moving into fall. Foliage remained attractive after bloom cycle and persisted throughout the fall and early winter.
Habit and growth rate observations
As with all Epimediums, Amber Queen has a slow growth rate. The clumps can be sparse and loose or full and mounded. Plants ranged in size from 6 inches by 10 inches to 10 inches by 14 inches. Older foliage was removed in late winter or early spring before the new growth began.
Site preference – soil & light
Amber Queen tolerates clay to loamy garden soils and very dry conditions once established. Placed under an Oak, Norway Maple or a deep shade border, the plant had a good success rate.
Successes and possible drawbacks – how to overcome them
Give plant time to get established and mark location upon planting in garden. To stave off early spring frost damage, keep mulched as long as possible.
Notes from growers/retailers
Grow this plant on the dry side with low fertility. Its slow rate at production makes this a 2 year crop. Overall Amber Queen presents with low maintenance requirements. Keep plants cleaned and watch for Black Vine Weevil.
Good combinations
Brunnera macrophylla, Daffodils and Ajuga ‘Caitlin’s Giant’, Carex
Parting SHOT – the overall evaluation results were Good***
Epimedium Amber Queen is recommended for its long spring bloom-time and petite yet showy flowers as well as for its foliage. Slow growing, it is a wonderful groundcover or specimen plant for full shade and typically difficult spots under trees with dry shade conditions.
Evaluated 2009-2012
Euphorbia amygdaloides var. robbiae
Robb’s Almond Spurge
**
PRINTABLE PDF
Flower description / bloom time
The flowers bloom from April to the beginning of June. Clusters of lime green flowers with a disk-like bract [looks like a green collar] are borne on stems 12 to 18 inches tall.
Foliage interest—color/texture
Resembling Japanese Pachysandra, the whorls of glossy dark green leaves, to 2-inches long, were mostly evergreen except for the first year after planting.
Habit and growth rate observations
The foliage is only 8 inches high but slowly spreads by rhizomes to 2 feet, which makes it such a useful groundcover. It spreads quickly in moist, loose, organic soil.
Site preference—soil and light
Robb’s spurge prefers rich, moist, humus-rich soil in partial shade. It also did well in drier sites and in varying degrees of sun or shade.
Successes and possible drawbacks—how to overcome them
In USDA Zone 5, Robb’s spurge is best grown in a protected site where the winter foliage remains evergreen and can be fully appreciated.
Notes from growers/retailers
Propagation can be done by division or cuttings. It is best to plant liners in late summer.
Great combinations
Hosta fluctuans ‘Variegata’, Astilbe x arendsii ‘Fanal’, Pulmonaria ‘Majeste’
Parting SHOT”—the overall evaluation results were Fair **
While there is some concern in regards to this euphorbia’s hardiness, the unusual texture and flower color make it an interesting addition to a light shade garden. But buyers beware; our evaluation has shown that Robb’s spurge can go either direction, becoming aggressive and taking over, or not coming back the following year. And it does not flower every year!
Evaluated 2006-2009
Eurybia divaricata (syn. Aster divaricatus)
***
White wood aster is a native perennial found in the eastern U.S. and typically grows in the wild
in dry open woods, clearings, roadsides and woodland edges. It forms loose clumps with dark,
sprawling, sometimes zigzag stems up to 2.5′ tall. The plants provide nectar for pollinators and
seeds for songbirds.
Flower Description and Bloom Time
Plants are covered with small, 1/4-inch-wide white flowers from June through the first fall frost.
Although the flowers are small, the plants were covered. Flowering was rated Good.
Foliage Interest — Color and Texture
Evaluators liked the medium to deep green foliage and dark stems (described as black,
burgundy or red) that looked good throughout the growing season. Leaves are fine to medium
textured, long and slender. The leaf stems (petioles) are red when first emerging. Gold fall color.
Evaluators rated foliage as Good.
Habit and Growth Rate Observations
Forms a mound that becomes about 18 inches tall up to 28 inches wide. One evaluator noted
that the plant spread a bit by runners.
Site Preference — Soil and Light
Grows in average, dry to medium, well-drained soil in part shade to full shade. Tolerates dry
conditions once established.
Successes and Possible Drawbacks
Tolerates drought. Evaluators called it a nice bright spot for fall in the shade garden. Plants have
a lax habit—If they get too tall they can flop. To prevent flopping, cut stems back to about 12
inches tall in early June. During heavy September rains, some leaves yellowed at one
evaluation site.
Notes from Growers/Retailers
Grows very strong in spring. Plants that have one year in containers look great the first thing in
spring and can be an early garden center seller. Growth regulators can severely stunt plants
and are not recommended.
Good Combinations
Asters are the backbone of many gardens in the late summer and early fall. Woodland aster is
suitable for open shade gardens, woodland areas, native plant gardens or cottage gardens. The
lacy texture of its leaves create a good contrast to hostas. One evaluator noted that the foliage
was stunning in combination with Brunnera ‘Jack Frost’ in a shaded site. In a sunnier area, the stems took on more color and paired well with Heuchera ‘Green Spice.’
Parting “SHOT” — The overall evaluation results were Good ***
Six evaluators trialed a total of 27 plants in locations from the far western suburbs, the Morton
Arboretum and the northern suburbs. The evaluation site conditions ranged from clay, loam soil
with good drainage; raised beds with infrequent irrigation, and, part-shade, well-drained organic
soil with periodic irrigation. A dependable perennial for sites with part shade and well-drained
soil.
Evaluated 2008-2011
Geranium ‘Orkney Cherry’
***
This compact hardy geranium hybrid is noted for its bronze foliage and pink flowers.
Flower Description and Bloom Time
The pink 5-petalled flowers have red veins and white throats. Some evaluators reported
that plants produced prolific bloom in June and then bloomed sporadically throughout
the summer. Other evaluators had flowers throughout the growing season and into late
October.
Foliage Interest — Color and Texture
Foliage is deeply lobed and bronze-green. The fine-textured foliage remains clean all
season. Burgundy fall color through October and November.
Habit and Growth Rate Observations
Plants produce a mound of foliage about 12 x 12 inches, although in one trial garden,
plants were 6 inches tall and 18 inches wide.
Site Preference — Soil and Light
Easily grown in average well-drained soils in full sun to part shade. Prefers moist,
organic soil. Established plants can be drought-tolerant.
Successes and Possible Drawbacks
The three-year period for this evaluation experienced drought. One exceptionally hot
March caused plants to emerge that were then subjected to freezing weather. Some
evaluators lost all three trial plants in the first year. Others had plants emerge in March
with unusually warm (80 F) temperatures, and the plants then disappeared in May.
Evaluators provided supplemental watering during drought conditions. Proper siting,
where the plant receives afternoon shade and medium moisture, will help. If summer
heat reduces flowering, plants can be cut back to rejuvenate, shape and/or encourage a
late summer/early fall rebloom. Although this plant is touted as deer and rabbit resistant,
deer did browse some flowers in one trial garden.
Notes from Growers/Retailers
Hardy in Zones 5 through 8. Provide additional water during periods of drought while
plants are establishing.
Good Combinations
Suitable for massing as a front border or edging plant in rock gardens and cottage
gardens. Consider companions such as coral bells (Heuchera), foam flower (Tiarella)),
dwarf goat’s beard (Aruncus ‘Misty Lace’) and other perennials that prefer afternoon
shade.
Parting “SHOT” — The overall evaluation results were Good ***
Although some evaluators lost all three of their plants due to summer drought or erratic
spring weather, plants that did survive performed well with supplemental watering. As
one evaluator noted, it’s a “great small edging plant with fall foliage color and long
bloom cycle.”
Evaluated 2011-2014
Geranium ‘Rozanne’
Hardy Geranium
***
Flower description / bloom time
Rozanne features lavender blue flowers with white centers and dark veins; the round, flat flowers are 1¾ inches in diameter. Rozanne blooms from June through September (and even beyond).
Foliage interest / color and texture
Deeply cut, medium green leaves are typical of hardy geraniums. Foliage did not attract much comment either positive or negative, however, foliage provides a nice backdrop for flowers and does not show any tendencies toward insect or fungal problems. Unlike many members of this genus, there was very little fall color reported.
Habit and growth rate observations
Make room in the garden for Rozanne as its mounding and sprawling habit can easily spread 24 to 30 inches across and reach 15 to 20 inches tall. Very little maintenance is required beyond a little tidying up of the foliage during the summer to keep the plant in bounds. One evaluator describes this vigorous habit as giving a casual flavor to the garden. Rabbits did not appear to favor this plant!
Site preference / soil and light
Rozanne is adaptable but evaluators had the best success in sites with sun to part shade. Protection from late afternoon sun is beneficial while too much shade results in poor flowering and form. Soil should be moist but well draining.
Successes and possible drawbacks—how to overcome them
Across the board our evaluators were impressed with the long period of bloom. You do not have to wait to see results. This plant puts on good growth the first year. A little light trimming in summer may be needed to keep Rozanne in bounds.
Notes from growers / retailers
Liner availability is somewhat limited. Several growers decided to grow this geranium over other geraniums mentioned below because it is more vigorous. Bare root plants potted in April can be ready in mid-May. However, another grower states that it is slow from a 2-inch plug and may need five to six weeks to get to the edge of the pot. All mentioned that pruning is helpful to keep the plant compact.
Best combinations
Rozanne looks sensational paired with yellow flowering perennials such as Hemerocallis ‘Happy Returns’. Alternatively, you could draw out the lavender tones in Rozanne by planting it with deep purple foliage such as Eupatorium rugosum ‘Chocolate’ or a plum-colored coleus.
Parting SHOT”—the overall evaluation results were Good ***
With its long bloom time, good blue flowers, and healthy foliage, Geranium ‘Rozanne’ makes quite a statement in the garden and was rated as Good.
Additional Notes:
•Geranium Rozanne holds up through the season better then ‘Johnson’s Blue’ and ‘Brookside’. Unlike Rozanne, these Geraniums usually need a hard cut back after flowering at the end of June or early July to rejuvenate the foliage.
•The plants we evaluated were originally received as ‘Jolly Bee, a cultivar that has been recently proven through DNA testing to be the same as Rozanne. Subsequently, ‘Jolly Bee’ has been removed from the market. Given that these two cultivars are the same plant, we reassigned our findings on ‘Jolly Bee’ to Rozanne.
Evaluated 2003-2006
Helleborus Winter Thrillers™
**
‘Winter Thrillers’ is a series of hellebores that offers different colored blooms that range
from single-flowered greens to double pinks.
Flower Description and Bloom Time
Flowering begins in April as the new foliage emerges. The 2.5-inch wide flowers were
both single and double. Some plants in evaluators’ gardens had cream-colored flowers
tinged with green and burgundy spots. Other flowers were yellow or purple fading to
green.
Foliage Interest — Color and Texture
Leaves are mostly 5-lobed with deep separations between some leaflets. They create a
coarse to medium texture. Leaflets are 7 to 10 inches long and medium to dark green.
New foliage emerges red before turning green. It then stays evergreen well into the
winter. According to one evaluator, “The narrow leaflets are distinctive from other hybrid
hellebores.”
Habit and Growth Rate Observations
The plants were slow growing and ranged in size from 10 to 14 inches tall and 12 to 16
inches wide. Plants formed a nice mounded mass by midsummer.
Site Preference — Soil and Light
Prefers partial shade with well-drained, clay-loam soil. Good drainage is important.
Because flowering was sparse for some evaluators, amending the soil with organic
matter before planting is suggested.
Successes and Possible Drawbacks
Plants offer about two months of bloom. Faded, spent flowers remain on the plants. Plants were
slow to establish and flowering was sparse on young plants, so gardeners need to be patient.
Notes from Growers/Retailers
Little maintenance is needed other than removing spent leaves in spring.
Good Combinations
Pair hellebores with other perennials that prefer light shade and well-drained soil, such as
Hosta, Epimedium, Geranium and spring-flowering bulbs.
Parting “SHOT” — The overall evaluation results were Fair **.
Evaluated 2011-2014
To the Top
Heuchera ‘Lime Rickey’
Lime Rickey Choral Bells
***
Photo courtesy of Walters Gardens
Flower description / bloom time
The white flowers are very small on slender 18-inch stems that rise above the mounded foliage. Most evaluators did not consider the flowers as significant. Two commented that their plants did not flower at all.
Foliage interest—color/texture
Heuchera ‘Lime Rickey’ has bright chartreuse leaves that are rounded with wavy edges and each leaf is about 2 inches in diameter. The bright color and the ruffled texture stand out in the shadier garden. Two out of six evaluators had some black spot on the leaves.
Habit & growth rate observations
Comments on growth habit were varied. Some evaluators described the full, mounded habit as excellent and lasting well into winter. However, some of the other evaluators experienced slow growth, failure to thrive and winterkill. At its best ‘Lime Rickey’ was 6-10 inches tall and 32 inches wide.
Site preference—soil and light
The three evaluators who had success with this plant had partially shaded conditions and dry to moist, but well drained soil. The three evaluators who reported poor results had very dry conditions with no supplemental water and/or slightly sunnier location.
Successes & possible drawbacks—how to overcome them
When not affected by leaf spot, the chartreuse leaves are the standout feature of this plant. Foliage holds up well into December and new growth emerges early in spring. Clean up of dead leaves in spring and removal of spent flowers were the only maintenance tasks mentioned. ‘Lime Rickey’ was not browsed by rabbits or damaged by slugs.
Notes from growers/retailers
This coral bell can be susceptible to rust and rotting. Growers recommended preventative fungicides and monitoring salts and moisture. Although it is a very slow grower, it always looks good in containers.
Best combinations
Athyrium filix-femina ‘Frizelliae’, Carex morrowii ‘Ice Dance’, Polygonatum odoratum ‘Variegatum’
Parting SHOT”— the overall evaluation results were Good. ***
The final evaluations were sharply divided. Three of the six evaluators rated the plant ‘Excellent’ and three rated it ‘Fair’, which gave an average rating of ‘Good’. Close attention to soil and light conditions were the determining factors for success.
Evaluated 2005-2008
Heuchera ‘Obsidian’
Obsidian Coral Bell
****
Flower description / bloom timeObsidian coral bell blooms sporadically in early summer with tiny white baby’s breath-like flowers on slender stems about 12 inches above the showy foliage.
Foliage interest – color/texture
Glossy, purple-maroon, scallop-edged foliage holds its color all season. Solely as a foliage plant this coral bell stands out boldly in any setting.
Habit & growth rate observations
Plants form robust mounds reaching 6 to 10 inches tall by 8 to 12 inches wide. In flower, plants are 12 to 15 inches tall.
Site preference – soil & light
Prefers moist, well-drained soil and full to partial sun exposure.
Successes & possible drawbacks – how to overcome them
Foliage remained clean throughout the trial and no pest or disease problems were observed. Coral bells tend to heave out of the ground over winter; correct by gently tamping plants back into the soil. Crown rot can be a problem so ensure soil is well drained. Mulch can be added, but keep it away from the crown. Deadhead flower stalks after bloom to tidy-up the plant.
Notes from growers/retailers
Plants are finished in approx. six weeks. Pot plugs in early spring to late summer. Plant in a well-drained mix and allow drying out between watering.
Good combinations
Carex, Hosta, Aruncus aethusifolius, Astilbe chinensis varieties, Alchemilla mollis
Parting SHOT – the overall evaluation results were Excellent
This scallop-edged, lustrous dark purple coral bell is very reliable and a wonderful contrast plant for shade gardens. Described as robust by evaluators—a word not often used to describe coral bells! The lack of foliage problems and good winter survival are positive attributes of Obsidian.
Evaluated 2005-2008
Iris x robusta ‘Gerald Darby’
Gerald Darby Iris
**
American irises, Iris versicolor and Iris virginica. ‘Gerald
Darby’ is noted for its violet-blue flowers and dusky purple
spring foliage. This plant is touted for its use in sunny sites
near ponds, water gardens and moist borders.
Flower Description and Bloom Time
Purple flowers with yellow-splashed sepals (falls)
appeared on purplish-black stems. Flowering began in
early June and persisted for about two weeks. One
evaluator recommended removing the spent flowers in
midsummer.
Foliage Interest — Color and Texture
In spring, the leaves are a dusky purple tipped with green.
Although one evaluator noted that the iris, which was
planted in part shade, did not exhibit purple leaves,
another found the purple leaves “very desirable.”
Habit and Growth Rate Observations
Plants ranged in size from 8 to 24 inches wide and 24 to
35 inches tall. Some plants flopped by midsummer.
Several plants were slow to establish.
Site Preference — Soil and Light
Grow this plant in medium to wet soils in full sun to part
shade. It may be grown in 2 to 4 inches of shallow
standing water or a very moist border.
Successes and Possible Drawbacks
Soils must be consistently moist and should not be
allowed to dry out. Site in full sun, moist soil and mulch
with leaf mould.
Notes from Growers/Retailers
N/A
Good Combinations
Can be combined with any other moisture- and sun-loving
plants, such as hibiscus, swamp milkweed and canna
lilies.
Parting “SHOT” — The overall evaluation results were
poor. *
This plant was evaluated from 2012 to 2015 at four sites in
Chicago’s western and far northwestern suburbs with a
total of 12 plants in the trial. By the third year of the
evaluation, only five of the 12 plants survived. Although
the evaluators did not recommend this plant, some noted
that the lack of overall vigor may have been due to the
size of the transplants and their small root systems. One
of the four evaluators recommended the plant for its purple
spring foliage that held onto its color into mid-summer as
well as for its attractive flowers.
evaluated 2012-2015
To the Top
Knautia macedonica ‘Mars Midget’
Mars Midget Knautia
***
Flower description / bloom timeBurgundy/ maroon pin cushion-like blooms averaging 1″ across. Flowers heavily end of May through June then sporadically until frost. Deadheading promotes repeat blooms and tidies up overall appearance. Very attractive when in bloom.
Foliage interest – color/texture
Foliage presents with neat clean, silvery green basal mounds round out as the season progresses. Evaluators agreed this plant can look a little ratty at times due to its loose habit. No disease or pest problems.
Habit and growth rate observations
Compact but inconsistent growth habit. All evaluators agreed that this plant has a leggy and loose habit and is a slow grower. The average size after 3 years was 18″ x 15″ There is little evidence of reseeding but is not bothersome.
Site preference – soil & light
Performs well in full sun and light shade. Withstands several soil conditions from clay to loam and dry to moist. This is an excellent plant for tough spots.
Successes and possible drawbacks – how to overcome them
This cultivar has a better habit and stays within its growing space unlike the straight species. Plant tends to lack luster out of bloom so removal of the spent blooms will keep this plant looking fresh.
Notes from growers/retailers
Easy to grow in a container yet slow to fill out. Even though it is a low maintenance grower too much water will rot the crown. For retailers, this is a hard sell when not in flower.
Best combinations
Geranium ‘Rozanne’, Salvia, Coneflower. Best planted by, or intermingled with perennials that support or serve as a backdrop. Consider white or pastel perennials so burgundy flowers will really stand out.
Parting SHOT – the overall evaluation results were Good***
Very attractive plant in bloom and recommended as a team member versus a specimen in the garden.. The flower color and long bloom time are also noteworthy.
Evaluated 2005-2008
Phlox divaricata ‘Plum Perfect’
Plum Perfect Woodland Phlox
**
Flower description / bloom timePlum Perfect’s flowers area a lavender- plum purple with a darker red purple eye zone blooming Late May into June. The flowers have a slight vanilla fragrance and attract butterflies.
Foliage interest – color/texture
The foliage on this Woodland Phlox is a fine textured medium to dark green. Burgundy tones come up in cooler spring or fall weather.
Habit and growth rate observations
Phlox ‘Plum Perfect’ has a loose, open growth habit ranging in evaluator gardens from 5-7 inches tall and 7- 20 inches wide. Only one evaluator noted that it had vigorous growth but was not invasive. Others noted a struggling growth habit and some floppiness.
Site preference – soil & light
This Phlox prefers part shade with 3-4 hours of sun. Most were grown in well drained but moist, clay loam soil.
Notes from growers/retailers
Growing tips include placement in dappled shade and good air circulation to reduce potential for powdery mildew. On the retail shelf these plants can be cut back after flowering for fresh growth.
Successes and possible drawbacks – how to overcome them
Deer love this Phlox and will graze this plant in early spring but it will rejuvenate buds and bloom. See next pix. Deadhead and apply supplemental water to keep this plant looking good all summer.
Best combinations
Phlox ‘Plum Perfect’ works well in the garden with other spring blooming plants: Brunnera, Polemonium, Ajuga, Tree Peonies, Tiarella and Daffodils.
Parting SHOT – the overall evaluation results were Fair
At the end of the evaluation period only 7 of 15 Phlox that were planted were still alive. Only one evaluator was completely successful with this plant and most noted that it was nothing special and overall a poor, weak performer
Evaluated 2007-2010
Ruellia humilis
Wild Petunia
**
Flower description and bloom time
This prairie native has light lavender petunia-like flowers that are 1 ½ inches in diameter. Wild petunia blooms sporadically from June through October; flowers usually fall off cleanly so deadheading is unnecessary.
Foliage interest—color / texture
Wild petunia’s fuzzy green foliage remains ornamental throughout the entire season.
Habit and growth rate observations
The low sprawling growth habit, 6 to 8 inches tall, will trail across or climb up and over depending on the neighboring plants.
Site preference—soil and light
The wild petunia enjoys full sun and moderate soil types; however, it will tolerate dry soils after becoming established.
Successes and possible drawbacks—how to overcome them
The trailing habit and tendency to self-seed can be a deterrent for some gardeners. When planted in adverse conditions like outcropping in a rock garden, the trailing habit can be a used to soften the edges. Also works well as a groundcover or in combination with other aggressive perennials.
Notes from growers / retailers
Ruellia is slow growing and unattractive in the container in spring. By midsummer the plant is fuller but still somewhat leggy. Best results in containers are achieved if the plants are kept on the drier side. Wild petunia is pest-free in containers and in the garden.
Best combinations
Wild petunia is best planted with drought tolerant plants such as prairie dropseed [Sporobolus], sedum, and daylilies.
Parting SHOT” —the overall evaluation results were Fair **
Due to its tendency to self-seed everywhere, it was given a rating of Fair in the overall appearance category. Not a good plant for the typical backyard garden, but a good pick for a tough site; e.g. a parking median bed. While limited in its applications, Ruellia humilis does fill a need in some gardens. Its trailing habit, drought tolerance and soft violet, long-blooming flowers make it appropriate for the rock garden or the drought-resistant prairie. Its lengthy bloom time will add color to your garden for much of the summer into fall!
Evaluated 2004-2007
Sanguisorba ‘Red Thunder’
Red Thunder Burnet
**
PRINTABLE PDF
Flower description / bloom time
Dozens of burgundy-red, knob-shaped flower heads on wand-like stems, to 30 inches tall; blooms in late July through September.
Foliage interest—color/texture
The foliage is pinnately compound. Each medium green leaflet is 2 inches long, lightly textured and toothed. However, when the Japanese beetles start eating holes in the leaves, they become brown and unsightly.
Habit and growth rate observations
Generally, plants took a couple of years to establish, and were described as thin and ‘wimpy’ in first year but ranged from 36 to 46 inches tall and 24 inches wide in the third year. Plant habits were adversely affected by Japanese beetle damage, rabbit browsing, and wind damage.
Site preference—soil & light
‘Red Thunder’ grows best in full sun to light shade in average well-drained soil and needs extra water during periods of drought.
Successes and possible drawbacks—how to overcome them
The biggest drawback to this plant is its attractiveness to critters like Japanese beetles and rabbits. It is one of the first plants in the garden that Japanese beetles go to when it starts to bloom. This is a nice filler plant with hundreds of tiny button size flowers held above the foliage.
Notes from growers/retailers
The flowers are not showy enough to attract the average garden center buyer.
Best combinations
Rudbeckia fulgida ‘Goldsturm’, Hemerocallis (pink or gold varieties), Allium senescens ssp/ montanum ‘Summer Beauty’, Miscanthus sinensis ‘Morning Light’, Geranium ‘Rozanne’.
Parting “SHOT”— the overall evaluation results were Fair **
‘Red Thunder’ can be a lot of work and probably best for an experienced gardener or collector. It can be useful as a filler plant where its lacy foliage and elongated button flowers can be used to highlight other bolder flowered and foliage plants. Its downfall is that it is a major food source for Japanese beetles and rabbits.
Evaluated 2005-2008
Silene caroliniana var. wherryi ‘Short and Sweet’
Silene ‘Short and Sweet’
*
Silene caroliniana can be found in rocky, calcareous
woods and outcrops from New Hampshire to Ohio and
south to Missouri and Alabama. It is not found in Illinois.
Flower Description and Bloom Time
Pink round flowers with wedge-shaped petals less than an
inch wide appear from late May through early June (about
a two-week bloom period). A cultivar of a native, ‘Short
and Sweet’ has flowers that attract nectar-seeking insects
and butterflies. The sticky flowering stems give this plant
the common name “catchfly.”
Foliage Interest — Color and Texture
Tufts of narrow, lance-shaped green basal leaves (up to 4
inches long) with smaller paired stem leaves.
Habit and Growth Rate Observations
During the first year of the trial, plants grew anywhere from
3 to 6 inches tall to 6 to 10 inches wide.
Site Preference — Soil and Light
This silene is often found in dry, rocky or sandy forests, as
well as barrens and areas with limestone outcrops. All of
these habitats indicate the plant’s need for good drainage
so that it does not remain wet for any extended period of
time. Grow in bright shade to full sun.
Successes and Possible Drawbacks
All the plants died by the third year of the evaluations.
Notes from Growers/Retailer
Hardy in Zones 4 to 7. Touted as a native plant substitute
for Dianthus because of the similar appearance.
Good Combinations
If you decide to try this plant, combine it with native sedum
(Sedum ternatum), columbine (Aquilegia canadensis) and
native violets.
Parting “SHOT” — The overall evaluation results were
Poor. 1/2 star
This plant was evaluated from 2011-2014 at four sites in
Chicago’s western suburbs and the North Shore. Although
this cultivar is described as long blooming, compact and
easy to grow, all 12 plants in evaluators’ gardens were
dead by the end of the trial.
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Symphyotrichum oblongifolius ‘October Skies’
(formerly Aster oblongifolius ‘October Skies’) Aromatic Aster
***
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Flower description / bloom time
October Skies is a selection of a native to the northeast and has masses of small [about one inch] soft lavender-blue daisy-like flowers with yellow centers that bloom late August into October.
Foliage interest / color and texture
The foliage is narrow creating a fine texture. The gray-green color is pleasing all summer and no powdery mildew was reported. Evaluators rated the foliage as good and praised it for its lack of disease issues. It is also aromatic when touched. In all but one site, this aster was not browsed by deer or rabbits.
Habit and growth rate observations
October Skies has a medium growth rate and is supposed to achieve mounds under two feet. But in some garden sites the plants became large masses approximately 30″ x 45″ – perhaps due to planting in overly rich soil [see site preference]. The habit tends to be a little floppy or sprawling by the end of the season. All plants survived except in one location where deer decimated the plants and they died out by year two.
Site preference / soil and light
Aromatic aster does best in full sun, with dry to average soils. Those grown in part shade or fertile, moist soils were more sprawling.
Successes and possible drawbacks—how to overcome them
The floppy late-season habit is a definite drawback. This could potentially be overcome by good pruning practices earlier in the season. Cutting the whole plant back by one-half around July 1 is suggested. Also, some evaluators rated this plant less floriferous and more sprawling by the third year. Other evaluators had better success with drier soil. Also, the blue flowers late in the season were judged a plus.
Notes from growers / retailers
Plugs were reported to finish in 4 to 5 weeks after rooting. To promote more compact growth, plants should be pruned or pinched by one half. Most growers reported that plants did over-winter in production but one grower did not have this success. Another grower reported that the plant was a prolific ‘re-seeder’ —this was not reported by those who trialed the plant.
Best combinations
October Skies looks great with ornamental grasses and other late-season, sun perennials and also looks good in naturalized settings.
Parting SHOT”—the overall evaluation results were Good ***
While Symphyotrichum oblongifolium October Skies has its drawbacks, it still received a good overall rating for the profusion of flowers produced in fall. So with a little foreknowledge of soil and light preferences, a gardener should have success using this aster.
Evaluated 2003-2006
Veronica longifolia ‘Eveline’
Eveline Speedwell
****
Flower description / bloom timeEveline speedwell blooms mid to late summer with some re-bloom in September. The flowers are pink-purple on a tapering four-inch spike. Repeat bloom is more consistent when spent flowers are deadheaded.
Foliage interest – color/texture
Dark green, disease-resistant foliage stays shiny and clean late into the season. There is no significant fall color.
Habit and growth rate observations
Plants grow 24 inches tall by 15 to 18 inches wide. Very upright habit does not flop.
Site preference – soil & light
Grow in full sun to part shade in average garden soils. Eveline is also very drought tolerant.
Successes and possible drawbacks – how to overcome them
Eveline is an easy to care for perennial that attracts butterflies and hummingbirds.
Notes from growers/retailers
Eveline is good in containers and has a long shelf life in the nursery. It roots easily from cuttings. From a #30 cell plug, it takes eight weeks to finish.
Good combinations
Calamintha nepeta ssp. nepeta, Carex sprengelii, Sesleria autumnalis, Achillea varieties.
Parting SHOT – the overall evaluation results were Excellent ****
Eveline speedwell was recommended by all evaluators because of the long bloom time and its disease resistance.
Evaluated 2003-2006
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Veronica ‘Purpleicious’
spike speedwell that is noted for its long period of bloom.
Flower Description and Bloom Time
Flowers were given high marks for repeat bloom.
Evaluators characterized its flower color as a purple-pink,
jewel-toned violet and rich pink-violet. Peak bloom took
place in June-July, but some flowers were still present in
September.
Foliage Interest — Color and Texture
Medium-textured, glossy dark green foliage with little leaf
spot.
Habit and Growth Rate Observations
Most evaluators rated the plant’s habit and growth rate as
‘Good.’ Plants typically were 20 inches tall to 12 inches
wide.
Site Preference — Soil and Light
Full sun, rich, well-drained soil with a medium amount of
moisture.
Successes and Possible Drawbacks
Deadheading spent flowers will prolong flowering into late
summer. Although leaf spot is common on some Veronica
cultivars, this one showed little to some leaf spot.
Supplemental watering was provided during periods of
drought. Root rot may occur in wet, poorly drained soils.
Notes from Growers/Retailers
N/A
Good Combinations
Veronica ‘Purpleicious’ can be used in rock gardens,
cottage gardens, perennial borders and as a pollinator-
friendly plant. Grow with other sun-loving perennials such
as Echinacea, Rudbeckia, Monarda, butterfly milkweed
(Asclepias tuberosa) and Sedum where the Veronica
blossoms can provide a vertical contrast.
Parting “SHOT” — The overall evaluation results were
Good***
Seven evaluators trialed this plant primarily in Chicago’s
western suburbs. Some of the positive comments were
“good flower color, long bloom time and little leaf spot” and
“a much-needed, compact spiky plant.” Others noted that
the flower color was similar to Veronica ‘Eveline,’ but that
the flowers were fuller and more robust on ‘Purpleicious.’
Evaluated 2007-2010
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Viola ‘Purple Showers’
Purple Showers Viola
**
‘Purple Showers’ viola is touted for its large, dark purpleflowers that appear from spring through fall atop compact
foliage.
Flower Description and Bloom Time
Lightly fragrant, deep purple-violet flowers appear in
spring and then sporadically throughout the season,
providing a soft show of color. The flowers fade to
lavender. Although flowering in one trial garden (full sun
and well-drained soil) was prolific, the May flowering was
sporadic in the other gardens.
Foliage Interest — Color and Texture
Evaluators described foliage as nice, with crenellated
leaves of medium to deep green. In most of the evaluation
gardens, foliage remained green and disease-free through
fall.
Habit and Growth Rate Observations
Plants ranged from 3 to 5 inches tall and 5 to 6 inches
wide. Some plants that got leggy during the first growing
season were cut back, which allowed for a second flush of
flowers. Plants were slow to fill in or weak in most of the
evaluation sites.
Site Preference — Soil and Light
While some garden sites suggest moist sites for this plant,
others tout it as suitable for alpine/rock gardens, which
require dry soil. Full sun to partial shade.
Successes and Possible Drawbacks
According to one evaluator, “If used as an annual, this
plant would not disappoint.” In another trial garden, the
evaluator stated, “This has been a great shade plant, filling
in, gradually spreading and I would definitely recommend
it.” Others who trialed the plant had problems with rabbits,
poor drainage or poor winter conditions that led to the
plants’ decline. Watch for slugs. Cut back if the plant
becomes leggy.
Notes from Growers/Retailers
Keep dry, cut back halfway through growing season to
prevent plant from becoming leggy. Use slug traps if
needed.
Good Combinations
Use as a shade garden companion to Hosta, Astilbe,
dwarf daffodils, dwarf Aruncus and ferns.
Parting “SHOT” – the overall evaluation results were
fair. **
Only three of the 24 plants survived the 3-year trial period.
In one garden, plants formed a petite mass from the
original three plants. Those plants had been sited in an
area with good drainage, which appears to be key for their
survival.
Evaluated 2007-2010
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