Information Center

  • Garden Knowledge

Annual Care

Planting annuals can bring instant gratification for any gardener. Bright colors and countless  combinations and sizes can contribute to beautiful landscapes or container gardens.

Annuals are plants that complete their life cycle in one growing season. Planted from seeds or seedlings, most annuals flower continuously during the spring and summer and then die with the first hard frost in the fall. Some may go to seed and self-sow to continue the cycle the following year but for the most part you will have to plant annuals every growing season.

Annuals are popular because they provide gardeners with a way to change up the look of a landscape from one season to another. They are valued for their continuous flowering abilities and ease of care. In a landscape, they can be planted among perennials to lengthen bloom periods. Annuals are great for hanging baskets and mixed containers or adding splashes of color around patios and outdoor living spaces. Very little care is needed with the correct growing conditions: light, water, soil and fertilizer. Deadheading (removal of spent flowers) or trimming may be the only maintenance that annuals require to keep them vigorous and flowering for long periods of time.

Light
Annuals can survive in a variety of light conditions. Many will thrive and bloom best in full sun, while others prefer partial shade. Afternoon sun (12pm-4pm) is the strongest and most suitable for sun-loving annuals while morning sun/dappled sun is sufficient for shade-loving annuals.
See the list below for light requirements according to species.

Water
Annuals need about one inch of water per week. Try to keep the foliage dry during watering. If you must use an overhead sprinkler, use it early in the day so that the foliage will be dry by nightfall, lessening the chance of disease. Container grown annuals may require more water than those in the ground, especially as the season progresses and plants become more pot-bound. If you live in a very dry climate or if you are concerned about conserving water, choose annuals that are drought-tolerant such as portulaca, geraniums, dusty miller, and scavola. If your soil stays wet or boggy, try one of these varieties: fuchsia, nicotiania or pansy.

Soil
Whether your soil is sandy and well-drained or heavy and slower-draining, there are annual plants and flowers available for every type of garden. Most annuals will flourish in moist and well-drained mixes that have organic material/peat moss and added drainage material (perlite/vermiculite). If your soil is clay, you can amend it with compost or well-rotted manure. After the first year, you should need only a light reapplication in spring.

Fertilizers and Maintenance
The two primary reasons for fertilizing annuals are to encourage growth and create healthy, vigorous, attractive plants that will yield an abundance of flowers. Choose a fertilizer that is well-balanced or higher in phosphorus (P) and potassium (K). Too much nitrogen will result in lush green plants with very few blooms. Two types of annual fertilizers are granular, which slowly releases food over a period of about 4-6 weeks, or liquid, which requires application every week or two as needed.

Shade Annuals
Begonia
Browallia
Calendula
Coleus
Fuschia
Impatiens
Ivy
Lobelia
Nicotiana
Pansy
Snapdragon
Torenia (wishbone plant)
Vinca Vine

Sun Annuals
Ageratum
Alyssum
Bacopa
Calabrachoa
Cleome
Cosmos
Cuphea
Dianthus
Dusty Miller
Fountain Grass
Geranium
Gerber Daisy
Lantana
Marigold
Moonflower
Nasturtium
Nemesia
Petunia
Phox
Salvia
Scavola
Sunflower
Supertunia
Verbena
Vinca
Zinnia