Perennials Trial Report

North Carolina State University
Raleigh, North Carolina
2011–2013

JC Raulston Arboretum at
North Carolina State University
Raleigh, North Carolina

Ted Bilderback
Director

Bernadette Clark
Agricultural Research Technician

Department of Horticultural Science
JC Raulston Arboretum

Table of Contents

General Introductory Notes and Acknowledgements
Understanding Our Data
Climate Graphs
Plant Material Sources
Results

General Introductory Notes and Acknowledgements

The Perennials Trial was first planted in the Spring 2011. The Perennials Trial were created in direct response to grower, plant industry and homeowner interest. They are located adjacent to the Color Annual Plant Trials at NC State University within the JC Raulston Arboretum (JCRA) in Raleigh. The JCRA is a ten and a half acre site administered by the Department of Horticultural Science and located on 35° 47'N latitude, longitude 78° 42' W, with an elevation of 400'.

Plants to be entered into our trials are received in one of three way—seeds, rooted cuttings/plugs or finished plants/pot. Virtually all are grown within controlled greenhouse environments prior to placement in protected outdoor structures for hardening off. Plant spacing in the trials is based on the estimated mature size of entrant that fits to a 4' × 4' area or by the number of plants sent. Each entry is evaluated for two complete calendar years, being removed after the spring flush in year three. After the plants are established, they are evaluated for hardiness and landscape performance with ratings regularly taken.

Acknowledgements

We thank the vegetative and seed companies that participate in our trials. The services we provide would not be possible without the cooperation and support of these companies. We appreciate this confidence and trust and we look forward to continuing our partnership.

Lastly, we are thankful to other departmental staff and the volunteers of the JC Raulston Arboretum who assisted in transplanting and maintaining the plants … we couldn't have done it without you all!

Participants

2011

Danziger Flower Farm
Kieft-Pro-Seeds
PanAmerican Seed
Proven Winners

2012

Foremostco, Inc.
Sakata Seed America
Skagit Gardens

We also thank the following companies for their support of material donations:

• BASF, 26 Davis Drive, Research Triangle Park, NC 27709
• Harrell's, P.O.Box 807, Lakeland, FL 33802
• Fafard, P.O. Box 26, Anderson, SC 29622

Understanding Our Data

Cultural Data

Trials are conducted in amended beds. Prior to planting, beds are fertilized with 10-10-10 granular fertilizer and tilled. Depending on requirements plants are placed either in the shade structure or fully exposed in the sun. All plant material is mulched with composted leaf mulch to a 2"–3" depth after planting. Pre-emergent herbicides are used at the initial planting and repeated each subsequent spring/summer season. Hand weeding is done at all other times. Later in the season, a post-emergent herbicide application along the edge of the beds was done on an as needed basis. An in-ground irrigation system delivers 1"–1.5" of water to the beds each week. Plant height and width measurements (recorded in inches) are taken twice during the growing season, usually at the end of June and again at the end of July. Data was collected from a representative plant, not the largest or the smallest but an average plant. Dormant plants were cut back in the fall/early winter to clean up the area and reduce overwintering habitat for insects and diseases.

Evaluations

The purpose of our perennials trial is to evaluate the plant material under conditions unique to our location. Our summer growing conditions are typically hot temperatures with high humidity. There is little nighttime temperature relief/recovery; average summer nighttime temperatures can be in the 70s. Irrigation is required all season.

Plants were given a visual rating by the same person. The overall rating was based on plant performance and appearance, including floriferousness, plant size and shape, and freedom from insect and disease problems. The rating scale ranged from 1 (very poor) to 5 (excellent) with 0.5 unit increments possible; a 0 rating indicated that all plants of the cultivar trial died.

What do we look for?

• General Plant Growth - Healthy appearance, attractive foliage, uniform growth
• Flowers- Floriferousness, bloom duration, uniform color, does it hold up after a heavy rain
• Pests and Diseases- Any visible evidence of damage: distorted or chewed foliage
• Heat tolerance- do the flowers and plants hold up in the heat, does the flower color fade or stripe
• Hardiness (Survival)- determined (in the spring) by the number of plants that made it through or emerged after the winter

Installation Date

Most entries were planted into their permanent trial location on:

2011 entries on April 29, 2011, and the heuchera, which arrived during the heat of summer, were potted up and place in shade until early fall (2011) when they were planted in beds.

2012 entries on April 10, 2012, and the rose entries were planted on September 25, 2012.

Entries that did not survive

Died 2011 Summer

Armeria pseudarmeria 'Ballerina Lilac'/Ballerina®™ Lilac
Delphinium chinensis 'Diamonds Blue'

Died 2012 Summer

Dianthus (Bouquet™ Purple)
Heuchera (Kira™ Tropical Forest)
Lavandula angustifolia 'Ellagance Snow'/Ellagance®™ Snow
Scabiosa columbaria 'Mariposa Violet'

Died 2012 Fall

Phlox 'Shockwave'

The best way to really evaluate our trials is to come in person. The JCRA is open 365 days a year.

Average Monthly Precipitation and Temperature

Summer 2011 was extremely hot with long stretches of temperatures over 90°F and multiple days exceeding 100°F, including a record-breaking five consecutive 100°F+ days. This heat was followed by periods of normal temperatures with heavy rain.

The winter season (2011–2012) was very mild. During the month of December, we broke two high temperature records and had one tie for minimum temperature. In January, we experienced several periods of back-to-back nights with low temperatures ranging from 20°F–28°F. Our first and only snowfall occurred on February 19.

During the summer season of 2012 we experienced long periods of temps over 90°F with 10 days at/over 100°F. In the month of July, our average night temperature was 74°F. Periodic, heavy rainfall (over 8" in July and September) also plagued this season.

The winter season (2012–2013) was one of fluctuating temperatures. The early parts of the season (end of October, November and December) temperatures were slightly warmer than normal. January was mild but February began a cold period with March being unseasonably cold. The average temperatures in March were lower than our historical temperatures by double digits! We experienced three snow events.

Seed and Plant Material Sources

Danziger Flower Farm, 102 Doan Avenue North, Painesville, OH 44077
Foremostco, Inc., 8457 NW 66th Street, Miami, FL 33166
Kieft-Pro-Seeds, P.O. Box 335, West Chicago, IL 60185
PanAmerican Seed, P.O. Box 335, West Chicago, IL 60185
Proven Winners, 1021 River Ridge Lane, Saint Thomas, MO 65076
Sakata Seed America, 18095 Serene Drive, Morgan Hill, CA 95037
Skagit Gardens, 3100 Old Highway 99 South, Mount Vernon, WA 98273

Please get in touch with these companies if you have specific questions regarding individual species and cultivars.

Trial Results

Perennials Planted in 2011

Baptisia 'Lemon Meringue'
Decadence™ hybrid wild-indigo

Company

Proven Winners

Year Planted

2011

Height

34"

Spread

36"

Number Planted

4

Survival

100%

Comments

Flowers are a clear yellow color; blooms early- in April; foliage provides interest after bloom. We experienced a problem with genista broom moth caterpillars (Uresiphita reversalis); they ate all the foliage by July 2012, regrowth occurred in September 2012.

Echinacea purpurea 'Little Annie'
coneflower

Company

Proven Winners

Year Planted

2011

Height

17"

Spread

23"

Number Planted

9

Survival

67%

Comments

Well-branched, compact plants with a long bloom period; flower color is lavender-pink.

Echinacea purpurea 'PowWow White'
coneflower

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

17"

Spread

21"

Number Planted

9

Survival

22%

Comments

Well-branched, compact plants with a long bloom period; flower color is a clear white.

Echinacea purpurea 'PowWow Wild Berry'
coneflower

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

18"

Spread

19"

Number Planted

6

Survival

67%

Comments

Well-branched, compact plants with a long bloom period; flowers are an attractive rose-purple color.

Heuchera 'Alpine Forest'
coral bells

Company

Danziger

Year Planted

2011

Height

10"

Spread

21"

Number Planted

5

Survival

100%

Comments

Good fall foliage color; forms a neat mound of lobed, dark silvery-green leaves with dark purple undersides.

Heuchera 'Autumn Leaves'  
coral bells

Company

Danziger

Year Planted

2011

Height

10"

Spread

18"

Number Planted

5

Survival

20%

Comments

Good fall foliage color; forms a tidy mound of leaves that are red in the spring, turn taupe in the heat of summer, and deep red in the fall.

Heuchera 'Evergreen Forest'  
coral bells

Company

Danziger

Year Planted

2011

Height

9"

Spread

16"

Number Planted

5

Survival

100%

Comments

Good fall color—yellows and reds mixed in with the green leaves; has a mounding habit.

Heuchera 'Fern Forest'  
coral bells

Company

Danziger

Year Planted

2011

Height

8"

Spread

17"

Number Planted

5

Survival

60%

Comments

Good fall foliage color; forms a mound of green and silver leaves.

Heuchera 'Purple Rain Forest'
coral bells

Company

Danziger

Year Planted

2011

Height

9"

Spread

15"

Number Planted

5

Survival

100%

Comments

Good fall foliage color; forms a mound of purple with silver-cast leaves.

Heuchera 'Tropical Forest'
coral bells

Company

Danziger

Year Planted

2011

Height

4"

Spread

6"

Number Planted

5

Survival

0%

Comments

Died Summer 2012.  Forms an attractive mound of green leaves with a silver-cast.

Dianthus
Bouquet™ Purple dianthus

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

14.5"

Spread

11.5"

Number Planted

12

Survival

0%

Comments

Died 2012 summer. Compact mounding habit; fragrant flowers that are a deep rose color; long bloom period from spring to fall.

Dianthus 'Pomegranate Kiss'
dianthus

Company

Proven Winners

Year Planted

2011

Height

7"

Spread

20"

Number Planted

7

Survival

14%

Comments

Low maintenance; flower color is red with splashes of pink; a fragrant (spicy) double flower; blue-green, grassy foliage that keeps it's color year round; mounded form.

Gaillardia ×grandiflora 'Mesa Bright Bicolor'
gaillardia

Company

PanAmerican Seed

Year Planted

2011

Height

18"

Spread

36"

Number Planted

9

Survival

33%

Comments

Uniform and well-branched plants- do not lodge; flowers are a bright yellow with a red center ring that do not fade as the season progresses; long bloom season- from April through late fall.

Gaillardia ×grandiflora 'Mesa Yellow'
gaillardia

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

14"

Spread

30"

Number Planted

6

Survival

83%

Comments

Low maintenance; uniform and well-branched plants—do not lodge; flowers are a bright yellow that do not fade as the season progresses; long bloom season- from May to late fall.

Hibiscus 'Cranberry Crush'
hibiscus

Company

Proven Winners

Year Planted

2011

Height

36"

Spread

42"

Number Planted

4

Survival

100%

Comments

An abundance of large (7”–8” dia), deep scarlet red flowers on uniform plants; leaves have a reddish cast and are deeply lobed; colorful foliage for fall interest. We cut plants back after all leaves had dropped in the fall, but since this plant does not leaf out until spring, pruning foliage any time in the spring before new growth appears is acceptable. (The thick stems are woody, so a sharp pair of loppers is needed to cut through them).

Hibiscus moscheutos 'Luna Red'
hibiscus

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

36"

Spread

32"

Number Planted

4

Survival

100%

Comments

Large, dinner-plate sized (7”–8” dia), red flowers on uniform plants; individual flowers last only one day; slow to emerge in the spring but once new growth begins it leaps.

Hosta 'Autumn Frost'
hosta

Company

Proven Winners

Year Planted

2011

Height

6"

Spread

11"

Number Planted

7

Survival

100%

Comments

The leaves are an attractive frosty blue with a bright yellow margin; small light lavender flowers; struggled until this year (2013), when it finally started to shine!

Phlox paniculata 'Shockwave'
phlox

Company

Proven Winners

Year Planted

2011

Height

17"

Spread

11"

Number Planted

9

Survival

0%

Comments

Died fall 2012. Attractive, eye grabbing variegated foliage- the leaves are green with wide yellow margins; fragrant flowers that are a lavender pink color; plant has upright growth habit; didn't perform as well as expected—substantial winter loss but surviving plants were stunning.

Salvia nemorosa 'New Dimension Blue'
salvia

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

12"

Spread

19"

Number Planted

12

Survival

58%

Comments

Compact clumps of well-branched plants; deep blue/purple flowers on spikes borne above the foliage; interesting leaf texture; long blooming—from late spring through late fall.

Salvia nemorosa 'New Dimension Rose'
salvia

Company

Kieft-Pro-Seeds

Year Planted

2011

Height

12"

Spread

17"

Number Planted

12

Survival

8%

Comments

Compact clumps of well-branched plants; rose-pink flowers on spikes rising above the foliage; interesting leaf texture; long blooming—from May through late fall.

Leucanthemum superbum 'Banana Cream'
Shasta daisy

Company

Proven Winners

Year Planted

2011

Height

17"

Spread

20"

Number Planted

9

Survival

44%

Comments

Evergreen, compact clumper with dark green foliage; attractive butter-yellow flowers that bloomed June to mid-August.

Veronica 'Hocus Pocus'
speedwell

Company

Proven Winners

Year Planted

2011

Height

11"

Spread

21"

Number Planted

9

Survival

44%

Comments

Plants formed uniform clumps of green foliage; attractive long, purple flower spikes; Plants are evergreen; flowered from May to July/August.

Panicum virgatum 'Cheyenne Sky'
switch grass

Company

Proven Winners

Year Planted

2011

Height

36"

Spread

36"

Number Planted

6

Survival

50%

Comments

Maintenance free; red to purple panicles form on dense, upright clumps of foliage; the blue-green leaves turn red in early summer; fall interest; good texture.

Perennials Planted in 2012

Rosa 'Sunrosa Red'
rose

Company

Foremostco

Year Planted

2012

Height

12"

Spread

11"

Number Planted

9

Survival

100%

Comments

Disease resistant; low maintenance; small blossoms begin as coral colored buds; floriferous plant; mild fragrance.

Rosa 'Sunrosa Yellow'
rose

Company

Foremostco

Year Planted

2012

Height

12"

Spread

12"

Number Planted

9

Survival

100%

Comments

Disease resistant; low maintenance; petite, fragrant blossoms; floriferous plant.

Campanula 'Ringsabell Rose'
campanula

Company

Skagit Gardens

Year Planted

2012

Height

7"

Spread

19"

Number Planted

12

Survival

100%

Comments

Pendent rose pink bell-shaped flowers on slender stems; flowers are nicely displayed above the green foliage; vigorous growth—takes over an area.

Coreopsis 'Mercury Rising'
coreopsis

Company

Skagit Gardens

Year Planted

2012

Height

18"

Spread

22"

Number Planted

12

Survival

83%

Comments

Large, red colored flowers with a little yellow eye that don't fade in the sun and the heat; vigorous grower but compact; it forms an attractive well- branched mound; continuously blooming; plants are evergreen.

Primula polyanthus
SuperNova primula mix

Company

Sakata Seed America

Year Planted

2012

Height

3"

Spread

7"

Number Planted

27

Survival

96%

Comments

Shade garden; a mixture of clear, eye-catching colors (one color per plant): lavender, pink, red, violet-blue, white, or yellow, all with yellow centers; the flowers emerged in the center of wavy green leaves; low maintenance.