The Latest from the Midwest on CUPHEADepartment of Horticulture and Crop Science The Ohio State University There has been increasing interest in the past few years in new Cuphea to accompany the market of the well-known Cuphea hyssopifolia (False Mexican Heather) and Cuphea ignea (Cigar plant). Rick Schoellhorn's article (GPN April 2002 Vol. 12 No. 4) provided a general overview of some of the Cuphea species for use in crop mix diversification. At The Ohio State University Learning Gardens, we commenced trialing of Cuphea species last year in our 2002 Trials. We are fortunate to be located adjacent to the Ornamental Plant Germplasm Center (OPGC). Vegetatively propagated germplasm was obtained from the OPGC in cutting form in February 2002 and seed maintained accessions were obtained from the North Central Regional Plant Introduction Station (NCRPIS) -USDA/ARS, Ames, Iowa in January 2002. Our species trial was designed to test this "new"germplasm alongside Cuphea currently available in the industry. Our goal was to evaluate the accessions for ornamental value, either for use "as is", or for possible incorporation into breeding programs. 2002 TRIAL: Our 2002 Trial commenced in May, and was carried through November. We evaluated 53 different Cupheas comprised of ~25 different species. Plants were grown in our Departmental greenhouses, and outplanted in mid-May to a full sun location in the raised bed portion of our trial area. Evaluations were performed on a monthly basis, with the main season evaluation occurring at the end of August. Plants were left in-ground thru November to evaluate fall flowering and plant cold hardiness. The top 14 selections of 2002 were the basis of the 2003 trial, the results of which we are presenting here. Results from the 2002 trial, complete with individual accession photos, can be accessed at http://floriculture.osu.edu. 2003 TRIAL: Stock plants of the 2002 selections were overwintered in the greenhouse and vegetative cuttings were taken on March 4 and grown on to 6" pot size. Plants were transplanted to raised beds on May 19. Watering was provided as needed via an automatic overhead watering system. Fertilization at 200 ppm N of a 20-10-20 fertilizer was applied via Dosatron at time of transplant, and then monthly until mid August. No mulch was used. Weather. Summer 2003 was unusually cool and wet for this central Ohio area. The first month post-planting was cool and moist, and plants exhibited minimal growth. This was followed by two weeks of oppressive heat and dry conditions. The rest of the summer had cooler than average temperatures and above average rainfall. Evaluations. Due to the slow start, no June evaluation was performed. Subsequent evaluations took place mid-month in July, August and September. The following criteria were evaluated on a 1 - 5 basis (1 = poor, 5 = excellent): Flower number, flower quality, foliage (plant habit and vegetative quality), and an overall rating. The overall rating took all factors, including plant uniformity as well, into consideration. Final plant height and diameter were recorded at the end of the season in mid-September. Results. Most of the selections re-screened this year performed in a similar manner to 2002, albeit the milder, wet weather conditions this year. Table 1 lists average plant height and diameter. Table 2 provides the quantitative results of the evaluations performed mid-month in July, August, and September. The table is ranked in descending order of the "Overall" September rating. Following are some qualitative descriptors of the accessions, with the accessions listed in descending order of the September 2003 overall rating. C. purpurea, 'Firecracker' . "Wow!!" was the immediate response when one member of our evaluation team looked at these flowers. This is one that really attracts people's attention. Beautiful, bright/brilliant flower color - purple with deep rose-red. Flowers are borne on one side of the stem and at tips. Flowered well all season, and numbers increased even more in late summer to fall. Nice for hanging baskets and containers or at the edge of raised beds. Currently available in the industry through Ball Floraplant. C. ignea,'David Verity' . Nice! A solid performer. This is just a great plant. Consistent scarlet-orange flowers are a bit larger in size and number than the typical species "cigar plant". Dark green foliage. It is taller than C. ignea species: an upright shrub 2 1/2 - 3 feet tall. Works well in containers as well. This is usually listed as C. ignea, but is actually a cross between C. ignea and C. micropetala. Currently available in the industry. We obtained ours as rooted plants from Select Seeds. C. hybrid, Ames 22422 . Nice flowers -deep rose-red petals with purple interior and tube. Flowering continues well late into season. Mounds to 2 feet. C. cyanea, Ames 4946 . Unique flower- pink tubes, yellow at ends, with two maroon petals and protruding red stamens. Nice red-pink pubescence on stems and leaf petioles. Nice contrast. Vegetatively can be "gangly". Try using in mixed containers as taller component plant. Possibly try plant growth regulators to improve habit. Watch...It may be more susceptible to diseases than other cultivars in this study. We lost a few trial plants to disease as well. The only Cuphea in this year's trial to suffer any mortality. It has breeding potential. C. hyssopifolia, 'Allyson' . One of the most common Cuphea currently on the market, this Mexican Heather has been a good performer in 4 straight years of annual trialing here at The Ohio State University. This purple flowering "contained shrub" is an excellent form for borders, containers, etc. Flower number does fluctuate throughout the season, and flower numbers were low at the September evaluations. The nice texture and habit compensate for the lack of flowers at certain times. Currently available in the industry. C. species, Ames 23677 . A new accession with possibilities. Small but abundant light purple flowers consistently throughout the season. Nice spreading low grower, lending itself to multiple uses...containers, hanging baskets, edges of raised beds, and even as a groundcover. In containers, keep feed consistent to maintain better foliage color. Otherwise, virtually no maintenance is required on this plant. C. varia, PI 607939 . Nicely contrasting flowers and foliage; delicate soft lilac flowers against blue-gray-green foliage. Nice texture- "wispy". Upright, controlled habit, lends itself for usefulness in containers by providing a bit of height. Does well as in-ground, too. Does self-seed quite a bit. Of particular note....this was the most cold hardy of all Cuphea trialed here last year in 2002. It survived the first few hard freezes we had last November. We will be watching it again this year. C. hybrid, Ames 22423 . Very similar to Ames 22422, but flower color not quite as vivid, and foliage struggles more...foliage color can appear "washed out". C. ignea . "Cigar plant". The species type widely available on the market, with bright orange tubular flowers darkly tipped. Nice compact habit. Flower numbers were a bit low in trial here this year. Currently available in the industry. C. hybrid, ėPurple Trailing' . Spreads well, but flower number very low until late summer to Fall. Somewhat diminutive flowers are a deep purple and attractive. Lends itself for hanging basket, container use. Currently available in the industry. C. hybrid, Ames 22287 . 'Starfire' . Released as a hybrid by the USDA in 1995. It is a cross between C. ignea and C. angustifolia. Flower best described as a pink "cigar plant" flower. Good tough plant, that can be used in containers as well as in-ground. This year flower numbers were not high enough to balance out the vegetative growth. Flower numbers were better in 2002. A bee magnet. C. micropetala, Ames 26109 . Upright "shrub" with beautiful glossy foliage. Flower tubes are in shades of orange to yellow, few in number main season, but increased in late season. In last year's trial, most flowers occurred in October. Potential. Is taller...3 to 4 feet. C. x purpurea, Ames 26110 . ėGeorgia Scarlet'. Nice flowers - deep pinkish-red with purple and good flower number. The vegetative portion did not perform well again here this year; the foliage continues to go downhill as the summer progresses. Currently available in the industry. C. palustris, Ames 17817 . Can function as a groundcover! Very vigorous vegetatively. Flowering is almost exclusively in September and October, with a very low number of small white/lilac flowers during the main season. In last year's trial, very profuse flowering commenced in October, producing a carpet of flowers which was quite beautiful. Final Comments. In the last ten to fifteen years, we have witnessed the advent of numerous new floriculture crops in the market. This tendency towards the new and different has not slowed down and we should expect this trend to continue. In the hands of a good breeder (or breeding program), Cuphea may become an important component of the crop mix that many growers produce. The variability of this genus is such that some day in the near future, we may see Cuphea used in hanging baskets, mixed containers, as bedding plants, or as ground-covers. Acknowledgments. We would like to acknowledge Dr. David Tay and Susan Stieve of the OPGC for providing vegetative germplasm and resource information, as well as for their help in the main season evaluations both years. Further information on the OPGC can be accessed at http://opgc.osu.edu. We would like to acknowledge Dr. Mark Widrlechner of the NCRPIS, USDA/ARS, Iowa State University, Ames, IA for providing seed germplasm and resource information. Thanks to Possum Run Greenhouses Inc., Bellville, OH and Timbuk Farms Inc., Granville, OH , for providing some of the industry entries. Thanks also to Dr. Richard Criley of the University of Hawaii and Dr. Peter Konjoian for their assistance in the main season/final selection evaluation in 2002. And, a big thank you to our Annuals Team of Master Gardeners , who helped in all phases of this trial. |
