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

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. However, information on garden performance of different species and cultivars for the mild winters in Alabama is needed to help consumers make plant purchasing decisions that will be successful in the home landscape environment. AAES researchers evaluated more than 300 bedding plant cultivars of seven different plant species during the winter of 1996-97 using cultural practices typical in the home landscape setting.

Pansies have been developed in such a wide range of types and flower colors that they have won the hearts of southern gardeners and expanded the southern growing season to a year-round endeavor. As a consequence, efforts are underway to develop additional annual species for the fall market. Dianthus, snapdragons, and many others have potential as fall bedding plants, and seed companies are developing cultivars for planting during the fall.

Consumers typically purchase cool-season bedding plants for the home landscape from late September to mid November. 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 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 that 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. One year may have periods of extreme cold followed by a warm spell, while others may be relatively mild. Changeable winter conditions challenge many cool-season bedding plants to remain healthy and bloom abundantly. 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 by a hard freeze or prolonged cold. The purpose of the research was to determine the overall winter performance of cool-season flowering annual plants. Results generated from this study will assist Alabama consumers in bedding plant selections for winter landscapes.

Bedding plant cultivars are frequently developed and marketed in a series. Cultivars in a series share common characteristics, such as height, 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.

AAES researchers evaluated 312 cultivars from seven different bedding plant species at the E.V. Smith Research Center in Shorter during the winter of 1996-97. The Research Center is located 26 miles east of Montgomery. Seeds for the trial entries were donated by several companies and plants were grown by Wright's Greenhouse and Nursery, Inc., a nearby commercial transplant producer. Every effort was made to grow the plants using cultural practices that the average homeowner might use. 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.

All bedding plants were grown in full sun. Rainfall was supplemented using overhead sprinkler irrigation to provide an equivalent of one 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 two weeks from October 31, 1996, through April 24, 1997, using a 0 to 5 scale (see Table 1 for rating descriptions). Flowering plants were rated primarily on their floral displays, while size, shape, and freedom from insect or disease blemishes also were considered. 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.

Table 1. Average Rating for the Best 19 Johnny-jump-ups in the 1996-97 Winter Trial

Cultivar	Flower color	Avg. rating1
Penny Azure Wing	blue	3.8
Penny Violet Beacon	purple	3.7
Penny Violet Flare	purple	3.7
Penny Primrose	pink	3.5
Blackjack	black	3.4
Felix	Yellow	3.1
Springtime Violet	purple	3.0
Alpine Summer	yellow	2.9
Fanfare White Blotch	white	2.8
Springtime Pure White	white	2.7
Alpine Wing	bicolor	2.7
Springtime Rose Blotch	rose	2.6
Springtime Deep Blue	blue	2.6
Fanfare Mixture	mix	2.6
Springtime Clear Blue	blue	2.6
Springtime Yellow Marble	yellow	2.5
Springtime Azure Blue	blue	2.5
Springtime Red	red	2.5
Springtime Mixture	mix	2.5
1Rating system: 0 = plant died; 1 = 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; 5 = superior floral display and sufficient foliage display.

Eight of the 10 best performing winter annuals in 1996-97 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 series or Springtime series; 19 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 entries in the trial in 1996-97, 51 rated 2.5 or higher. All cultivars rated 2.8 or higher are shown in Table 2. Though the cultivars in Table 2 are from a variety of sources, six cultivars are from the Universal series, three cultivars are from the Rally series, and two cultivars each are from the Accord and Baby Bingo series.

Two other species that may 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 will resume growth and flower early in the spring. The best performing China pinks were Floral Lace Picotee, Award Mix, and Duchess Mix, all 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 when there are few other plants growing.

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, reblooming 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 been focusing their efforts on 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 the southern landscape to provide critical information to the gardening public.