Here are some easy tips on how to grow Alcea plants: After the last frost, set out year-old plants 12-24 inches apart; dig well-rotted manure into soil. Use 2-3 in. organic mulch. Water daily at first, then twice a week, or more if very hot/dry.
Pronunciation: AL-see-uh or al-SEE-uh
Common Name: Hollyhock
Description: Old-fashioned favorites, Alcea plants reach 8-12 ft. tall and 3-4 ft. wide. Single or double spiked flowers in a wide range of colors grow on an upright stem with large, coarse leaves. Flowers bloom from the bottom up. Gardeners can choose from modern hybrids like miniatures (3-4 ft.tall) and the double flower (looks like a cabbage rose).
Origin of Plant: China
USDA Hardiness Zones: 3-8
Fertilizer Needs: 10-10-10 or 15-15-15. Twice a year: early spring and again in the fall.
Sunlight: Needs full sun.
Maintenance: High. Biennial Hollyhock plants act like perennial plants if deadheaded and cut down to the base when flowers are done. Starting in June, pull off all yellow leaves, also leaves ruined by Japanese beetles and/or rust. Destroy rust-infested leaves. Cut out all old flowering stems and old leaves in late summer when flowering stops. New leaf growth holds up over mild winters, or if kept covered by snow. In spring, pull off winter-damaged leaves. Tall Alcea plants, if cut down once or twice before flowering, will grow back as later-blooming shorter plants that don't need staking. (Flower spikes will also be shorter.) Protect these perennial plants from high winds to keep them from getting broken.
Pests/Diseases: Rust, weevils, Japanese beetles, cutworms, slugs, and caterpillars. Avoid overcrowding when planting: damp, still air is a breeding ground for rust. Avoid over-wet or over-dry conditions; both weaken these perennial plants. Water the soil around the plant; rust grows on damp or wet leaves. Destroy all cuttingsâ€“never compost!
Wildlife Value: Alcea brings bees, butterflies, and hummingbirds into the garden.