J. Raymond Kessler, Jr., Bridget K. Behe, and James S. Bannon

Twenty years ago, few gardeners considered planting bedding plants in the fall. However, planting cold-hardy annuals to provide color in the winter landscape has become very popular with the gardening public in Alabama. This practice is primarily due to the popularity of pansies, though several other cold-tolerant species can be grown in the same time frame. Pansies have been developed in such a wide range of types and flower colors that they have won the hearts of southern gardeners, extending the southern growing season to a year-round endeavor. As a consequence, efforts are underway to develop other annual bedding plant species with potential for the fall market such as Dianthus, snapdragons, and many others.

Consumers typically purchase cool-season bedding plants from late September to mid-November for planting in the home landscape. Bedding plant cultivars are frequently developed and marketed in a series. Cultivars in a series share common characteristics such as size, growth habit, or disease resistance, but differ from each other in flower color. The name on the label often begins with the name of the series followed by the flower color, e.g. ‘Bingo Blue’. The majority of bedding plants are purchased in plastic market packs from garden centers, grocery stores, mass market outlets, and home centers. These retail outlets often maintain large displays containing a wide selection of bedding plants in a variety of types and flower colors. However, this selection often contains types and cultivars which are popular, but may not perform well under the environmental conditions of Alabama winters.

Winter weather in Alabama is highly variable from year to year with one year having periods of extreme cold followed by a warm spell, while other years may be relatively mild. Changeable winter conditions challenge many cool-season bedding plants to remain healthy and floriferous. In one year, a cool-season plant may maintain foliage and flowers throughout the winter months while in another year, the plant may be killed to the ground by a hard freeze or prolonged cold. Therefore, information on performance of different species and cultivars for the mild winters in Alabama is needed to help consumers make plant purchasing decisions for home gardens and commercial landscape environments. The purpose of this research was to determine the overall winter performance of cool-season flowering annual plants.

METHODS
The trial evaluated 312 cultivars from seven different bedding plant species at the E.V. Smith Research Center in Shorter, Alabama, during the winter of 1996-97. The Research Center is located 26 miles east of Montgomery, Alabama. Seeds for the trial entries were donated by several companies and transplants were grown by Wright’s Greenhouse and Nursery, Inc., a nearby commercial transplant producer. Raised flower beds were tilled and amended with agricultural limestone and slow-release fertilizer (18-6-12) according to soil test recommendations. After transplanting, the flower beds were mulched with pine bark. No additional fertilizer was applied during the season. No fungicides or insecticides were applied during the trial period. Every effort was made to grow the plants using cultural practices that the average homeowner might use.

All plants were grown in full sun with rainfall supplemented using overhead sprinkler irrigation to provide an equivalent of 1 inch of water per week. No deadheading of spent flowers or other maintenance was performed on any of the plants with the exception of hand weeding.

Plants from each entry were evaluated every 2 weeks from October 31,1996 through April 24, 1997 using a 0 to 5 scale. Flowering plants were rated primarily on their floral displays, while size, shape, and freedom from insect or disease blemishes were also considered. A rating of 1 indicated a small display of foliage with no flowers present; 2–adequate amount of foliage with one or two flowers present; 3–sufficient foliage and floral display to be attractive in the landscape; 4–above average floral display and sufficient foliage display; and 5–superior floral display and sufficient foliage display. A rating of 0 indicated the plant had died. Any plant with an average rating of 2.5 or higher over the trial period could be considered acceptable in the landscape and would be a worthwhile addition to a garden located in temperate zone seven or eight.

RESULTS
Eight of the 10 best performing winter annual species were Johnny-jump-ups, Viola tricolor (Table 1). These plants are pansy-like violas with smaller, but more numerous flowers than pansies. Many of the best performing Johnny-jump-ups were from the ‘Penny’ or ‘Springtime’ series. Nineteen of the 35 entries rated 2.5 or higher. All cultivars in the top 19 were compact, low to the ground, and full of small, attractive, pansy-like flowers during most of the winter months.

Pansies are the traditional cool-season annual for fall planting in the southeastern United States. Of the 199 pansy entries in the trial in 1996-97, 51 rated 2.5 or higher. All cultivars rated 2.8 or higher are listed in Table 2. Though the cultivars in Table 2 are from a variety of sources, six cultivars are from the ‘Universal’ series, three cultivars from the ‘Rally’ series, and two cultivars each from the ‘Accord’ and ‘Baby Bingo’ series.

Based on the results from this study, two other species that should be considered for winter planting in Alabama gardens are China Pinks and Snapdragons. China pinks, Dianthus chinensis, are marginally hardy in central Alabama. During mild winters, the plants can maintain foliage through the season. Even in severe winters, foliage may be killed to the ground, but plants will resume growth and flower early in the spring. The best performing China pinks were ‘Floral Lace Picotee’, ‘Award Mix’, and ‘Duchess Mix’ with ratings of 2.3. The China pink cultivars in the trial did not perform as well as in past years, but provided very attractive mid-winter green or blue green foliage throughout the winter.

The best performing snapdragon, Antirrhinum majus, was ‘Silks White’ with a 1.9 rating, while ‘Tahiti Red’, ‘Tahiti Rose’, and ‘Silks Yellow’ tied for second place with a rating of 1.7. Scores for snapdragons reflect the fact that they do not bloom during winter months, but contribute pleasant green foliage to the landscape until they resume flowering in early spring. Unfortunately, re-blooming in the spring of 1997 occurred after the winter annual study was concluded.

Seed companies and retailers are constantly developing new bedding plant cultivars and products. Recently, they have focused their efforts on the growing southern market by developing new bedding plant types and cultivars for the cool season in the southeast. Ongoing research is needed to evaluate these new products for their performance in southern landscapes to provide ciritical information for the gardening public.