Tall spires of hollyhocks are traditional anchors in old-fashioned cottage gardens. These short-lived perennials or biennials produce masses of color in summertime, tempting playful children to pick the blooms and create tiny dolls in flower-petal skirts. However, the blooms fade quickly and rust is a continual problem. Cutting back hollyhocks encourages a second flush of growth and controls rust.
Wait until hollyhocks have stopped blooming in late July or early August. In hot temperatures the lower leaves wilt and drop off. However, new growth appears at the base of the plant and produces a second crop of flowers. The "Sunset Western Garden Book" suggests gardeners cut the hollyhocks down to the new growth to encourage reblooming, then apply a balanced fertilizer according to the manufacturer's directions.
Cut the hollyhock stalks 3 inches above the ground in fall, after the second bloom cycle. Cover the root crown with 2 to 3 inches of mulch.
Dispose of the cuttings in the trash. Rust produces dark yellow pustules on the underside of leaves, and hollyhock leaves are particularly disease-prone. Remove diseased leaves throughout the growing season.