Flowering annuals or bedding plants are favorite among homeowners. They are inexpensive and produce an abundance of brightly colored flowers from spring to frost. Some are even winter-hardy if protected by a light mulch.

Annuals complete their growing cycle within one growing season. They are usually purchased in early spring and planted as soon as the last frost is past. Several annuals, such as pansy, snapdragon, stocks and sweet alyssum will withstand a light frost and can be planted earlier for establishment during cool weather.

The annuals industry has grown tremendously in the last several years. The impatiens plant is very popular due to its versatility, offering brilliant summer-to-fall bloom in shady beds, borders and containers. Other common annuals are geraniums from cuttings and seed, petunia, marigolds and fibrous begonias.

Planting Site:

Annuals grow best when the soil in the planting site has been prepared beforehand to receive the transplants. Planting sites should be well drained and in full sun or moderate shade, depending on plant species preference. Adequate drainage is very important, as plant roots fail to thrive in wet soil.

Adjust the soil to a pH of 6.3 to 6.7 for best growth. Highly organic soils can range from pH 5.7 to 6.0. Amend the soil with high quality compost. At planting, break apart soil root masses slightly to prevent "root balling." This procedure will ensure rapid root expansion into surrounding soil. Water plants after planting to hasten root establishment.

Post-Purchase Care:

Plant annuals immediately after purchasing. Transplants, if held for a few days before planting, must be kept watered, since the small cell-packs dry readily. Place plants in a shaded area and remove dead flowers as needed to prevent decay if planting is delayed. Do not store plants in the garage where gasoline engines are started. Ethylene gas, a product of combustion, can cause leaf drop and flower injury. High temperatures and low-light conditions will also lead to rapid deterioration of plants.

Site Selection:

Moist Location: Angel Trumpet, Forget-Me-Not, Hibiscus

Poor Soil: California Poppy, Celosia, Cosmos, Snow-on-the-Mountain

Sunny Location: Aster, Baby's Breath, Bachelor Button, Calendula, Celosia, Cosmos, Dianthus, Flowering Kale, Flowering Cabbage, Gazania, Geranium, Larkspur, Marigold, Morning Glory, Portulaca, Nasturtium, Pansy, Petunia, Poppy, Salvia, Snapdragon, Statice, Strawflower, Verbena, Zinnia

Shade or Semi-Shade: Annual Phlox, Balsam, Begonia, Bellflower, Calendula, Coleus, Dwarf Lobelia, Forget-Me-Not, Impatiens, Larkspur, Nasturtium, Nicotiana, Pansy, Sweet Alyssum, Verbena, Wallflower, Wishbone Plant

Dry Locations: Ageratum, California Poppy, Cockscomb, Coreopsis, Cosmos, Portulaca, Petunia, Statice, Swan River Daisy, Verbena, Zinnia

Post-Planting Care:

• Fertilize at time of planting by using a controlled release fertilizer product that will feed all season or use a liquid with 20-20-20, 23-19-17 or a similar liquid fertilizer on a bi-weekly basis.
•  Remove dead flowers and broken branches weekly to reduce botrytis fungus buildup and keep plants healthy.
• Use a soaker hose to wet the soil when watering--avoid overhead watering which wets the foliage.
• Root rot problems are occasionally unavoidable when growing annuals in the home garden. Reduce problems by emphasizing the cultural methods of good site preparation with adequate internal moisture drainage.

Sources of Plants:

Purchase plants from greenhouses in the spring. The quality of plant material will vary from location to location. Quality will also be reflected in price. Annuals can also be started from seed indoors or directly sown in the garden. Sowing indoors is done about eight weeks before the average date for the last killing frost in spring. Seed started earlier will often be leggy and not suitable for transplanting. Keep soils between 72 to 75 degrees F for optimum rapid germination. Direct sowing can be done when soils warm to at least 60 degrees F. Small seed will present more establishment problems than larger seed.

Adapted from Charles T. Behnke, Ohio State University Extension, 2000