While chrysanthemums are easy to-grow perennials, pinching, watering, and fertilizing are necessary to insure a good flower display in the fall.
Pinch newly planted and established mums from late spring to midsummer. Remove the stem tips when the shoots are approximately 6 inches tall. New lateral branches will develop along the stems. Pinch again when these new shoots reach a length of 6 to 8 inches. Pinching can be done with your fingers or a pair of clippers. Continue pinching until late June or early July. Pinching results in bushy, compact plants with additional flowers.
Water mums thoroughly during hot, dry weather. Water deeply once a week. Avoid wetting the foliage when watering to discourage possible disease development. To conserve soil moisture, mulch chrysanthemums with 2 to 4 inches of grass clippings, wood chips, or other materials. The mulch also helps control weeds.
Encourage plant growth with a monthly application of fertilizer. Use a water soluble fertilizer according to label directions or dissolve 1 tablespoon of a complete garden fertilizer, such as 5-10-5, in one gallon of water.
This article originally appeared in the May 17, 1996 issue, p. 78.