Black Hollyhock Plants

Flowers and Seeds

• The black hollyhock is well-known for its distinctive dark maroon to almost black petals. The flowers grow in clustered spikes from a tall stem. Black hollyhocks bloom from June through August and attract hummingbirds and butterflies. Seeds are produced in the late summer and early fall and will self-seed if allowed.

Foliage and Stems

• Black hollyhocks feature dark green, heart-shaped leaves with three, five or seven lobes. The lower leaves are larger and rough, with upper leaves becoming progressively smaller. Foliage is often subject to attack by disease and pests. Stems can grow to heights of 5 to 8 feet.

Propagation

• Black hollyhocks thrive in full sun and well-drained soil in zones 2 through 9. Seeds should be planted in August or September for blooms the following summer. Once established, the black hollyhock will readily self-seed itself each season. Branches can be pinched one to two times early in the season to create shorter plants with more branches.

Pests

• Black hollyhocks are susceptible to a variety of pests and diseases including rust, leaf spot, anthracnose and attacks by spider mites and Japanese beetles. Pests and diseases affect the foliage but generally leave the flowers unharmed. Prevention is the key to treating plant pests and diseases. Check plants for signs of pests and disease before purchase. Remove diseased parts of plants, handpick larger pests like beetles and keep the area surrounding the flowers weed-free. Fungicides and insecticides like neem oil can be used in extreme cases, but be sure to follow instructions.