Note: The JCRA launched a new Web site on March 1. Please visit us at http://jcra.ncsu.edu. This site, http://www.ncsu.edu/jcraulstonarboretum/, is no longer being updated.

Summer 2002 Annuals Trial Report

North Carolina State University
Raleigh, NC
2002

Robert E. Lyons
Professor and Director

With Technical Assistance from
Bernadette Clark & Tim Ketchie

Department of Horticultural Science
JC Raulston Arboretum
Horticultural Research Series No. 157

Introduction and Cultivar Evaluation Criteria

The Annual Trial Gardens at NC State Univesity are located within the JC Raulston Arboretum, 4301 Beryl Road, in Raleigh. The JCRA is an 8 acre site administered by the Department of Horticultural Science and located on latitude 35° 47'N, longitude 78° 42'W with an elevation of 400 feet.

Seedling and vegetatively derived plants were grown to transplant size in 2.5 inch x 2.2 inch containers, with most planted outdoors on 25 April 2002. The remaining selections were planted shortly thereafter when transplant survival would be best. Plant spacing in the trials was 18 inches x 24 inches (in-row x between-row spacing). Seven plants of each entry were used to evaluate landscape performance. Plants were rated weekly as described later in this report.

We gratefully acknowledge the support by Fafard, Inc. (P.O. Box 26, Anderson, SC 29622), Dillen Products, P.O. Box 738, Middlefield, OH 44062, The Scotts Co., 14111 Scottslawn Rd., Marysville, OH 43041, and the North Carolina Commercial Flowers Growers Association.

This year's Annual Trials Student Assistant was Tim Ketchie, an undergraduate in the Department of Horticultural Science at NCSU. Tim did an exceptional job of maintaining the overall appearance of the trials area, overseeing the health of the entries, and helping with our Field Day. We are deeply grateful for his input and contributions during the 2002 season! The assistance of Ingram McCall, Bradley Holland, Lee Davis, Mitzi Hole, Anne Calta, Valerie Tyson, Chris Glenn, and Robbie Wooten is acknowledged with much appreciation!

Hoffman Nursery <www.hoffmannursery.com> of Bahama, NC; Campbell Road Nursery of Raleigh, NC; and Heronswood Nursery <www.heronswood.com> of Kingston, WA, also donated selected ornamental plant materials for our beds...thanks!

We are especially thankful to other departmental staff and the volunteers of the JC Raulston Arboretum who assisted in transplanting and maintaining the annual beds throughout the growing season....we couldn't have done it without you all!

Robert E. Lyons
Professor and Director
919/515-1192
e-mail: bob_lyons@ncsu.edu

Bernadette Clark
Horticuture Research Technician
919/515-1213
e-mail: bernadette_clark@ncsu.edu

Understanding Our Data

Plant Height & Diameter at Maturity (in inches)
This measurement is taken near the end of the entire evaluation period.

Number of Weeks in Flower
Recorded as the total number of weeks in flower throughout the entire season. This should give you an idea of whether or not a plant is best used for the whole season or as a "fill-in" for special displays. Obviously, those species grown for foliage interest, e.g. Duranta erecta, alone will score poorly in this column!

Weekly Ratings
Plants were given a visual rating weekly by the same person beginning May 29, 2001 (three weeks after planting) through September 17, 2001 (16 weeks of observations.) The 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; a 0 rating indicated that all plants of the cultivar trial died.

Summaries of Weekly Ratings
Realizing that there are many species/cultivars which may do better in one part of the growing season versus another, we provide an "early season average" and "late season average" for each entry. The former is the average of the first 8 weeks of the evaluation period and the latter includes only the last 8 weeks. This information may be useful in planning short term plantings with high impact as well as for studying temperature preferences, life cycle changes, and/or the impact of photoperiod on plant performance. The "number of weeks rated above 3" gives you an idea of how consistently throughout the twenty weeks an entry is an exemplary performer.

The Lists In This Report

We list each of the above statistics (except the weekly ratings themselves) in all the reports (all provided as PDF files) that follow:

"The Top 10" – this list shows the species/cultivars with the top ten "All Season Averages." These were our top overall performers.

"Leaders of the Pack" – lists all species/cultivars with an "All Season Average" of 3.0 or better. We consider this the cutoff rating for a "significant performer." This list shows all your best choices for planting, listed by plant name.

"Leaders of the Pack – Early Season" – this shows entries with "Early Season Averages" of 3.0 or better based on the first 8 weeks of evaluation. This group may prefer cooler temperatures or only have a relatively short ornamental life, and might not show up on the "Leaders of the Pack" list above.

"Leaders of the Pack – Late Season" – this shows entries with "Late Season Averages" of 3.0 or better based on the second 8 weeks of evaluation. They may prefer very warm temperatures or flower as daylengths start to shorten, again precluding them from inclusion on the overall "Leaders of the Pack" list.

"Best of Breed" – shows the best performing cultivars in each species.

"Summary by Series" – groups the information for cultivar series where appropriate. This can be a quick reference for related cultivars as well as a handy tool to judge the general performance of an entire series offered by a breeder.

Want Additional Copies of this Report? Visit our Web Site!

www.ncsu.edu/jcraulstonarboretum

Sources of Seeds and Plants

AAS – All-America Selections, 1311 Butterfield Road, Suite 310, Downers Grove, IL

AT – American Takii, Inc., 301 Natividad Road, Salinas, CA 93906-1401

BALL – Ball Seed Co., P. O. Box 335, West Chicago, IL 60185

BEN – Ernst Benary of America, Inc., 1444 Larson Street, Sycamore, IL 60178-9705

BFP – BallFloraPlant, 622 Town Road, West Chicago, IL 63185

BG – Bodger Seeds Ltd., 1800 North Tyler Avenue, So. El Monte, CA 91733-3618

CRN – Campbell Road Nursery, 2804 Campbell Road, Raleigh, NC 27606

EAP – EuroAmerican Propagators, LLC, 32149 Aqueduct Road, P O Box 289, Bonsall, CA 92003-0289

FM – Farmen, P. O. Box 13408, San Luis Obispo, CA 93406-3408

FIS – Fischer USA, Inc., 2995 Wilderness Place, Suite 102, Boulder, CO 80301

GOLD – Goldsmith Seeds, Inc., 2280 Hecker Pass Highway, Gilroy, CA 95021-1349

Heronswood – Heronswood Nursery, 7530 NE 288th Street, Kingston, WA 98346

JCRA – JC Raulston Arboretum, Box 7522, North Carolina State University, Raleigh, NC 27695-7522

J&P – Jackson & Perkins Wholesale, P. O. Box 9100, Medford, OR 97501

PA – PanAmerican Seed Co., P. O. Box 438, West Chicago, IL 60185

SAK – Sakata Seed America, Inc., P. O. Box 174, Dry Ridge, KY 41035-0174

SYN – Syngenta Seeds, Inc., 5300 Katrine Avenue, Downers Grove, IL 60515-4095

The Average Monthly Temperature and Precipitation Values for the Summer 2002 Trials

Average Monthly Temperature

Precipitation

"Off the Cuff"

Summaries of Casual Observations from the Field Staff Summer 2002

In this section you'll find summarized comments from those we recorded throughout the growing season......kind of like a "between the lines" addition to the actual ratings found in this report. Our comments are in alphabetic order according to species; this list is not exhaustive since not all entries in our trials received particular comments.

Angelonia – as a group, the angelonias weathered the drought and hot weather extremely well. The best of our group by early September, in my opinion, was 'Angel Mist Purple Stripe'. Sturdy and heavily flowered, the flower color really stood out in the crowd and from a distance. Yet, which was the best......'Angel Mist Light Pink' was outstanding among them all.

Capsicum annuum (ornamental peppers) – Wow, here's another group of plants that is no newcomer to the garden, but the new cultivars coming available should revolutionize their popularity. I am specifically referring to 'Explosive Ignite' and 'Explosive Ember' which lit up our trials, particularly the latter half of the season. Heat seems to be its addiction and the drought did not seem to bother them at all. Best of all, their strong and vibrant dark purple foliage was more than a decorative backdrop to the purple, creamy, orange and red fruits......nothing short of fabulous! We'd like to see some serious interest in these plants!

Catharanthus roseus (vinca) – several species were well suited to our unusually hot summer and vinca was certainly one of them. One of the slower annuals to get going in the early spring, vinca jumps into action when warm weather finally sticks around. This year's standout was 'Big Ruby'. And while 'Victory Lavender' was not one of the best for all around performance, we particularly liked the unique flower color and felt it was worth mentioning.

Centaurea gymnocarpa 'Colchester White' – once again I find myself raving about this plant. Grown almost exclusively for its dusty silver foliage and spidery appearance, this "dusty miller on steroids" held on beautifully through our drought and heat. Neat and tight, most colors are set off even better with this plant as the backdrop or complement.

Cleome 'Linde Armstrong' (spider flower) – certainly an interesting form of the familiar heirloom, this cultivar was exceptionally lovely for the first half of the summer. It was always in flower and possessed attractive, darkly pigmented stems on compact plants. Unfortunately, as the summer languished, the flowering declined steadily, finally to a virtual standstill by early September.

Dahlia × hybrida 'Kingston Queen' – we thought we had seen the best of this group "evaporate" when we were hit with an unusually brutal double whammy of drought and mites/thrips this summer. Most of the cultivars we pinned out hopes on fizzled, but not 'Kingston Queen'. Its clean, dark, ruby foliage, and vigorous, sturdy habit reaching 3' were the perfect backdrop for lovely burnished orange flowers. I remain confident in this group of what I see as an underused landscape plant, despite the difficult year; they are just too beautiful to give up on! And I highly endorse the dark leaved cultivars like 'Kingston Queen'!

Datura 'Cornucopaea' (double purple angel's trumpet) – a perfectly confusing plant from a nomenclature standpoint but that didn't confuse the reactions of our visitors. They loved it. A real crowd pleaser that is always in flower, without the assistance of deadheading. Their "beaten egg white" texture and one-sided, deep purple appearance lit up the shrubby habit of the plant.

Impatiens hawkeri (New Guinea impatiens) – OK, OK, could I possibly let this report go by without some remarks about these wonderful plants? No! We were plagued this year with a disastrous infestation of thrips and mites on our impatiens, and I'm afraid our numbers will not give a fair assessment of the overall potential of our entries, except for the fact that they succumb to these pests. However, if I had to pick out some worthy entries despite our problems, I'd have to commend 'Celebration Neon', 'Celebrette Lavender', 'Sonic Fuchsia', and 'Super Sonic Lavender'. Hmmmm, the lavenders seem to have had an edge this year!

Ipomoea batatas (ornamental sweet potatoes) – OK, I'm partial to the 'Sweet Caroline' series since they originated right here at NCSU, but I think you'll agree with my enthusiastic endorsement once you try them. Our 'Sweet Carolina Bright Green' was the most vigorous but still more controlled than the familiar 'Sulfur'/'Marguerite', and you just won't find another cultivar with color similar to our 'Sweet Carolina Bronze'! Whether in the ground or in large containers, these plants are ornamental show stoppers and functional annual ground covers.

Ipomoea (morning glory) – not really sure of the species here, although I doubt it is either I. purpurea or I. tricolor, the new 'Good Morning' series of morning glories kept us guessing all season! Delighted to see some new introductions in this arena and anxious to see what improvements had been made, we watched this group carefully. At first we figured that we actually had complimentary plants for the ornamental sweet potatoes! The irregularly and broken variegated foliage, and sprawling, non-vining habit tailored these cultivars for similar landscape use. However, we were pleasantly surprised to see the decorative picotee styled flowers, although concerned that they were often disguised by the canopy. This behavior improved by late season as flower appearance increased dramatically, like most morning glories, and the foliage seemed to "loosen up."

Lantana camara 'Samantha' (variegated lantana) – what a great change up for a plant that is on the fast track for landscape use in the Southeast. 'Samantha' could easily hold its own even without a seemingly perpetual flowering habit; and you can add compact, low maintenance, and "border friendly" to its resume.

Lantana trifoliata (trifoliate lantana) – perhaps one of the more interesting tender perennials in our inventory this season, the trifoliate lantana had the flowering power of its L. camara cousin, but followed up with a lovely show of beauty berry-like fruits. In other words, they were purplish and beady, whose color almost mimicked that of its flowers, and held on elongated stalks. Visitors enjoyed their long lasting potential for garden interest, and true to form, they took off once the weather heated up.

Pentas lanceolata 'Variegata' (variegated pentas) – off to a slow start but once the hot weather kicked in, so did this plant. The crayon-red flowers were offset strongly against the creamy, light green, and darker green foliage....and they were always in flower. Well branched, strong and rigid, a powerful color combination for the landscape. It is not often that we get a plant with both attractive, omnipresent flowers and equally vibrant foliage.

Pennisetum glaucum 'Purple Majesty' (purple millet) – at last, a contending alternative for the deservedly popular Penniseutm setaceum 'Rubrum' (annual purple fountain grass). This brand new introduction for the public is sure to find a place fast in the collections of many gardeners. Unlike its fountain grass cousin, 'Purple Majesty' is stiff and erect, and strong and glowing in the landscape. We've admired it for years and are pleased to add to our list of favorites and highly recommended; it truly deserves its All America Selections Winner status!

Plectranthus – Man, have Swedish ivies come a long way, and we're probably talking about a complicated mix of species here. Here's another garden plant whose history goes back to the houseplant craze of the 70s. Well, I'm glad someone decided to remove the pot and place the plant in the landscape, and now we're even getting interesting flowers. 'Nicoletta' was a strong ground cover, compact, and still not in flower by early September; 'Mona Lavender' displayed lovely, dark green leaves and prominent flower spikes of its namesake's color late in the season; 'Zulu Wonder' and 'Nicodemus' were also well worth the time and worth our recommendation.

Portulaca 'Fairy Tales Cinderella' – I remember a type of paint used in the 70s known for it brilliant and almost halting colors.....we called it "dayglo." Well, with the introduction of this cultivar, I think the breeders have reproduced it in a flower! This uniquely double version of the well known moss rose was a trooper in the drought; grew rapidly and densely, and covered the ground just like a shag rug on fire! For the faint of heart, this is not for you, but why be faint of heart??

Rudbeckia hirta (blackeye Susan) – anyone who knows me also knows how much I admire and appreciate this North American wildflower when used in the landscape. There are some lovely cultivars being released, like 'Autumn Colors', who can indeed hold a candle to what I consider to be the "standard" of all R. hirta cultivars, 'Indian Summer'. Unfortunately, the ultra-dwarf cultivars self-destructed for us this year by going out of flower very soon and dying back badly; 'Cordoba', 'Toto Rustic', and 'Toto Lemon' all performed poorly this season.

Saccharum officinarum 'Pele's Smoke' (purple sugar cane) – for pure originality, this is a great plant. 'Pele's Smoke' is not out to dethrone annual purple fountain grass as the "ornamental landscape grass of choice," but I hope it will do a good job of enhancing the landscape with its tall, erect, statuesque, sturdy, dusty purple appearance. This is another tender perennial that is slow to start following installation, don't despair and don't give up. Once the summer warms up for good, so does the display of this plant. Propagates easily from mature cane cuttings, too. Marvelous!

Thunbergia alata (blackeye Susan vine) – if you had asked me 5 years ago for my thoughts on the potential for vines in the "annual" landscape, I might not have had much to say. And I never would have predicted that breeders would be putting any effort into improving what we've got already. Enter the cultivars 'Sunny Yellow Star' and 'Sunny Orange Wonder' for this long-time vine favorite......both needed a little "help" in getting started up their supports, but once there, look out! They laughed at the drought and heat, flowering nearly non-stop all season. We thought that the yellow version was a bit better performer in the landscape than the orange, and the numbers proved that out.

Final Comments......to close down this section, here are a few notes about some of our other entries worth noting; remember, I'm shooting from the hip here. The groundcover verbenas keep looking better and better for Raleigh, keep them coming; Peek-a-Boo spilanthes is a wonderfully weird plant that will likely find a comfortable home amongst devoted plant geeks! Melampodium 'Lemon Delight' is great in the early months, tends to crash later in the season....keep trying. Anisodentea 'Elegant Lady' performed well for us but I wouldn't call it "elegant." We found it to be stretchy and haphazard in habit, but interesting flowers.

Of course, the best way to really evaluate our trials is to come in person. The JC Raulston Arboretum is open 365 days/year from dawn to dusk. Don't forget to visit our Web site <www.ncsu.edu/jcraulstonarboretum>.

Winter Annuals Performance Evaluations

October 2001-March 2002
A Special Supplement to the Summer 2002 Trial Report

The 2001-2002 Winter Annuals Performance Evaluations report was originally included in the Summer Annuals Trial Report in 2002, however, it has been removed from this online report.

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