How to Grow Annual Geranium (Pelargonium)

Buy healthy, green plants with no signs of wilting or disease. Plants should be stocky with plenty of leaves. It's actually a plus if they don't have any flowers on them - they'll divert their early energy into root development rather than flowering.

Choose the right geranium for your needs. Zonal geraniums (Pelargonium x hortorum) have a tidy growing habit, reaching 1 1/2 to 3 feet tall. Ivy geraniums (Pelargonium peltatum) have glossy leaves shaped like those found on ivy, and their stems grow to 2 or 3 feet. Regal or Martha Washington geraniums (Pelargonium x domesticum) have large, showy clusters and wavy-edged leaves. Regals bloom so long as temperatures remain below 60 degrees at night. Geraniums bloom in a wide variety of colors, from red to pink to white, and all are excellent for container growth.

Plant geraniums in the spring after all danger of frost has passed. Choose a site in full sun, although in hot climates geraniums appreciate some afternoon shade.

Keep soil evenly moist.

Trim faded flowers to promote longer bloom.

Fertilize every four to six weeks or work a slow-release fertilizer (or plenty of compost) into the soil at planting time.

Tear out and discard plants after frost fells them in the fall, in Zones 2-9. In Zones 10 and 11, where these plants are perennials, allow them to overwinter. In these warm regions, when plants get spindly, cut them back severely or replant with cnew ones.