Cut back your healthy hollyhocks in early fall, after they have stopped blooming, if you do not want your plants to self-sow. Clip the main stalk down below the foliage line, until about 4 to 6 inches of the stalk remain.
Dress the stalk with straw or mulch about 6 inches deep. This helps protect the plant during the cold winter months.
Trim off any diseased or infected hollyhock leaves as they appear. Clear the diseased plant parts away from your garden and do not compost them. Hollyhock diseases such as rust can overwinter and reinfect your plants in the spring.