Hollyhocks are cultivated for their big, colorful, funnel-shaped summer flowers. Need rich, well- drained soil.
A. rosea. HOLLYHOCK. This old-fashioned charmer from the Mediterranean region is best against a fence or wall or at the back of a border. Old single selections can reach 9 ft. tall; newer strains and selections are shorter. Big, rough, roundish, heart-shaped leaves, slightly lobed, form a clump to about 3 ft. wide. Flowers are 36 in. wide along upright stems; they may be single, semidouble, or double in colors including white, pink, rose, red, purple, creamy yellow, apricot. 'Old Barnyard' mix grows 46 ft. tall; 'Happy Lights' are 57 ft. tall and rust resistant, 'Spring Celebrities' mix reaches 23 ft. with double flowers, and the 'Indian Spring' mix ranges from dark purple and pink to white. Chater's Double is a fine perennial strain; the 6-ft. spires have 5- to 6-in.-wide flowers. Biennials treated as annuals that bloom the first year from seed include 5- to 6-ft.-tall 'Summer Carnival,' with double flowers; and 2 -ft.-tall 'Majorette' mix.
A. rugosa. RUSSIAN HOLLYHOCK. Although from southern Russia and Ukraine, this hollyhock is a good perennial for the South. Similar to old single forms of A. rosea, the 6- to 7-ft. stems are topped with single, butter-yellow blossoms. Disease resistant.
Sow seeds in ground in late summer for next season's bloom; seed annual strains in early spring for bloom that summer. After flowers fade, cut stalks just above the ground; continue to feed and water plants to encourage late-summer or early-fall rebloom. Destroy any rust-infected leaves as soon as disease appears. Look for yellow spots on the leaf surface and orange spots with spores underneath. The spores are carried on the wind and will weaken a plant and destroy new growth. Remove infected leaves from the plant as well as from the mulch below. Also watch for slugs, snails, Japanese beetles.