Editors’ Note: This is the fourth in a six-part series on research being performed at Michigan State University in East Lansing.

research MSU Trials Report By Art Cameron

s the new annual plant trial director at Michigan State University, I was in rapid- learning mode during the 2009 growing season. But I was looking forward to watching, up close and personal, the performance and ornamental character of new annual introductions. In particular, I was interested in learning which annuals were both Atough and great performers, considering this has been a focus of mine through the years with herbaceous perennials and ornamental grasses. Rating every few weeks all summer long, I found plenty of interesting annuals well worth further consideration. And some were even tough enough to make it into my own home !

Plant Culture and Weather Texture and Form In 2009, all our annuals were transplanted Perhaps it is not surprising that many of our into ground beds between May 19 and June 1. top long-term summer performers have orna- Soil temperatures in mid-Michigan typically rise mental leaves, texture and form. above 60° F in late May. Plants were spaced on 8- Starting at the top of the list, alphabetically, is to 12-inch centers. Every other week, from June carex ‘Toffee Twist’. In mass, this plant sets up 25 to September 15, Chris Noffsinger (2009 trial a fi ne spray of texture that combines well with garden manager), Ashley Whalon (summer intern, color or other textural plants. I’ve grown ‘Toffee sponsored by Michigan Growers) Twist’ for years in my home garden alongside and I rated the plants as a group to reduce bias. herbaceous perennials and have found that it At the alternative rating periods, Ashley rated is perfectly tough and can often overwinter in the plants. Plants were subjectively rated based mid-Michigan. It is typically rated as hardy to on vigor and ornamental performance. Top per- USDA Zone 6. Carex are native to open areas formers received a 5 rating; plants with passable in New Zealand, thrive with full sun and well- performance received a rating of 3; and underper- drained soils, and tolerate a fair amount of forming varieties received a 2 rating. drought stress. In 2009, we tested nearly 400 annuals, about Many colocasia have performed well in Mich- two-thirds of which were grown in the ground. igan through the years and can provide a pow- (The other third were grown in containers.) In erful and bold tropical element to a garden. Some general, plants grown in containers outper- can grow to more than 6 feet tall by the end of the formed the same plants grown in the ground, season. Somewhat surprising to many, they do most likely because they were better watered not need to be grown in water, and in fact can be and fertilized than those in the ground. Ground fairly drought tolerant. ‘Heart of the Jungle’ was beds were hand watered as needed and ferti- the only cultivar submitted to our trials this past gated with 19-4-23 (250-ppm nitrogen) water- season and it put on a great show, particularly soluble fertilizer every two or three weeks. No when paired with cyperus ‘King Tut’. Cyperus, treatments were given this year for disease con- like colocasia, do not need constant moisture trol, and there was more root-disease pressure in and can easily be grown as bedding plants in our ground beds. climate. Several other colocasias have done well here in the past, including ‘Black Magic’, ‘Violet The Toughest Annuals at MSU Stem’, ‘Tea Cup’ and ‘Coffee Cup’. New cultivars Performance of plants grown in the ground seemed to give us a better indication of “tough- Carex ‘Toffee Twist’ and grasses ness” because they received less irrigation and Colocasia ‘Heart of the Jungle’ fertilization in our trials. Still, under these con- ditions, several plants we tested received ratings of 5 on nearly every rating date and averaged 4.7 or better (see Table 1). Each of these 24 plants looked great to the judges from less than a month after planting to mid-September. I think it’s fair to say that many home are looking for plants that provide interesting ornamental char- acters for most of the season without being too fussy in a garden setting.

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Top Tough Varieties Basil ‘Aristotle’ Coleus combination Genus Cultivar or variety Company Carex sp. ‘Toffee Twist’ Proven Winners Colocasia ‘Heart of the Jungle” Proven Winners Coprosma ‘Taupat Gold’ Plug Connection Cyperus papyrus ‘Baby Tut’ Proven Winners Cyperus sp. ‘King Tut’ Proven Winners Euphorbia ‘Breathless White’ Ball FloraPlant Euphorbia ‘Diamond Frost’ Proven Winners Ipomoea ‘Bright Ideas Lime’ Oro Farms Ipomoea ‘Bright Ideas Palmate Black’ Oro Farms Ipomoea ‘Chillin’ Blackberry Heart’ Proven Winners performed well the entire summer. Ipomoea ‘Chillin’ Blackberry Star’ Proven Winners Home gardeners can repeatedly Coprosma ‘Taupat Gold’ harvest the small leaves for Ipomoea ‘Illusion Midnight Lace’ Proven Winners spicing up their meals, and the Lobularia ‘Snow Princess’ Proven Winners plant will grow back quickly. Ocimum basilicum (basil) ‘Aristotle’ Floranova Perhaps a bit more bitter than a Petunia ‘Supertunia Vista Bubblegum’ Proven Winners Genovese cultivar, this is a nice Petunia ‘Supertunia Vista Silverberry’ Proven Winners edible selection from Floranova’s Plectranthus ‘Silver Crest’ PanAmerican Seed Vegetalis program. Sanvitalia ‘Garden Leader Gold’ Grimes Coleus is back! But it’s returned Solenostemon (coleus) ‘Kingswood Torch’ Proven Winners with a name change: Solenostemum scutellarioides. (What ever hap- Solenostemon ‘Royal Glissade’ Proven Winners pened to Coleus blumei? I’m sure Solenostemon ‘Henna’ Ball FloraPlant someone has a reason for changing Where’s the Color? Solenostemon ‘Red Head’ Ball FloraPlant the name, but I doubt I’ll ever com- It was hard to fi nd tough plants Solenostemon ‘Trusty Rusty’ Ball FloraPlant pletely understand.) Regardless of with bright splashy color displays Zinnia ‘Profusion Yellow’ Sakata Seed the Latin name, the new cultivars from late Juen through the entire are bold, vigorous and sun tolerant! season. Many more would have Table 1. Here are the top-performing annuals grown in ground beds in the 2009 Michigan State Many have been selected to with- made the grade if we had started University Trial . All plants received at least a 4.7 rating out of 5. Plants were numeri- stand the full elements of heat and rating in mid-July. With the longer cally rated based on performance (vigor, size and ornamental impact) every two weeks during the humidity. Several cultivars made season, the best of the best for our summer from June 25 to Sept. 15 it to the top of our list this year: trials included euphorbia ‘Diamond bred in Hawaii, such as ‘Hilo Bay’, All the ipomoea we grew this ‘Henna’, ‘Trusty Rusty’, ‘Red Head’, Frost’ and ‘Breathless White’. have been selected for more of a year performed very well. It’s really ‘ColorBlaze Kingswood Torch’ ‘Diamond Frost’ was released in clumping form that is less inva- more a matter of personal taste and ‘ColorBlaze Royal Glissade’ 2005 and has received any number sive in tropical parts of the world. chosing among the heart-shaped were essentially perfect all season. of accolades since then. This plant ‘Heart of the Jungle’ aggressively purple, dissected lime, or round, They were all at least 4 feet tall by really deserves the praise. It can sur- formed runners, but these are not a copper leaves! They all grew well September, and with absolutely no vive heat and drought and requires problem in a northern garden. in the full sun with limited water. detectable faults. Most all the other only low fertility. It epitomizes a Both Cyperus ‘King Tut’ and The two Bright Ideas introductions coleus varieties we trialed fell into the tough fl owering plant. ‘Breathless ‘Little Tut’ are great for garden tex- from Oro Farms were quite impres- “Best of the Rest” category, including Blush’ is a relative newcomer but ture. The straight species of each sive, as was ‘Chillin’ Blackberry several seed-propagated selections. seems to possess much of the posi- of these selections have long been Heart’. I’ve been wondering when One other new plant that pro- tive features of ‘Diamond Frost’. It a staple in southern gardens, and someone will breed one that we vided interesting foliage color and fi lled in fast and provided nonstop it’s great to see these more widely can harvest and eat at the end of tough character was coprosma color and texture all season long. distributed to northern gardeners. the season — added value for the ‘Taupat Gold’. Noticeably more vig- One somewhat surprising addi- ‘King Tut’ was easily 8 feet tall by ! orous than some of the other new tion to our best and tough annual the end of the season and there Speaking of edible, we found coprosma cultivars, it was defi - list is zinnia ‘Profusion Yellow’. were no noticeable effects of short that ‘Aristotle’ basil, a Greek-style, nitely eye catching in the ground This remarkable little zinnia pro- periods of drought stress. small-leafed form from Floranova, and in containers last season. duced nonstop from beginning

Ipomoea ‘Chillin’ Blackberry Heart’ Coleus ‘Henna’ Coleus ‘Trusty Rusty’ Zinnia ‘Profusion Yellow’

(Photo: Ashley Whalon) (Photo: Ashley Whalon) www.gpnmag.com May 2010 GPN 19 Great Petunias in Ground Beds Rating Cultivar Company research 6/25 7/8 7/27 8/12 8/27 9/15 ‘Suncatcher Red’ Ball FloraPlant 3 3 5 4 5 4 to end. It had a great habit that zinnias in adjacent beds were com- ‘Supertunia Vista Bubblegum’ Proven Winners 4 5 5 5 5 4 complements its showy fl owers. It pletely covered with mildew by ‘Supertunia Vista Silverberry’ Proven Winners 5 5 5 5 5 5 never collapsed or showed signs of the end of the season). ‘Profusion ‘Suncatcher Burgundy’ Ball FloraPlant 3 3 5 4 4 5 mildew in our trials (all the other Yellow’ held up through it all. ‘Ray Purple’ Danziger 3 3 5 4 4 5

Petunias We tested more than 50 petunia varieties in the ground in our 2009 trials. Many were excellent in con- tainers, only two made it to the top of our list when grown in the Euphorbia ground. As the season progressed, several petunias in our trials began to deteriorate in our beds. Unfortu- nately, after testing, our plant diag- ‘Hip Hop’ (PPAF) nostic center identifi ed Thielavi- opsis (black root rot) in these beds. In addition to a very low royalty rate, the Euphorbia ‘Hip Hop’ has While we were disappointed to fi nd this pathogen, we noticed that non-stop blooming of pure white flowers atop dark green foliage, two petunias, ‘Vista Silverberry’ and ‘Vista Bubblegum’, held up the which makes ‘Hip Hop’ a perfect accent to any poinsettia variety, entire season even while petunias particularly GroLink’s own VelocityTM series. on each side of them succumbed to disease. While we have no spe- RESERVE YOUR CUTTINGS TODAY! cifi c evidence that black root rot caused all of the disease problems we observed — or whether the Vista cultivars are truly resistant — it seemed a noteworthy observa- Poinsettia tion and may be of value for future ‘VelocityTM Red’ (PP17,522) testing and breeding.

‘Supertunia Vista Silverberry’

(Photo: Ashley Whalon)

‘Supertunia Vista Bubblegum’

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Other surprises in the garden

EDUCATION MERCHANDISING SHOWCASE IDEA EXCHANGES WORKSHOPS SEMINARS TOURS

grow in their garden. All would love to use less fertilizer, water 2010 and . When this is the objective, tough annuals fi t the bill, especially when combined with tough herbaceous perennials and ornamental grasses. We hope to At the Heart continue our quest to identify and select annuals that can survive and thrive under tough conditions. Tough annuals can be used in of it All marketing programs: At the 2010 California Spring Trials, EuroAmer- ican had a section of plants under a program named “Ecovation.” These plants were marketed as drought tolerant and tough, though the pro- TRADE gram focused largely on the Cali- SHOW fornia climate. It will be great to see this extended to rest of the country. The move toward more sustain- able landscaping could provide an impetus to expand breeding MEET SUPPLIERS priorities. I’d like to encourage breeders SEE NEW PRODUCTS will to take a closer look at tough ONE-STOP AND NEW VARIETIES annuals such as Verbena bonariensis SHOPPING or Datura spp. that grow in gardens with such little care! GPN

NETWORKING Art Cameron is director of the MSU Horticulture Gardens, trial garden director and professor of horticul- ture at Michigan State University. SHARE IDEAS He can be reached at cameron@ AND SOLUTIONS msu.edu.

MEET FRIENDS BUILD RELATIONSHIPS AND COLLEAGUES The Heart of Horticulture TM PREMIER INDUSTRY EVENT LearnMore *5,9  s#/,5-"53 /()/ For more information www.ofa.org related to this article, go to www.gpnmag.com/lm.cfm/gp051002

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