Chrysanthemums, commonly called mums, are perennial flowering plants that bloom in vibrant colors ranging from shades of white to dark burgundy. Many chrysanthemum varieties are rather cold-hardy and low maintenance. If given plenty of sunshine, most mums will bloom throughout the growing season, some even up to the first frost. Many chrysanthemum varieties are selected especially for their prime blooming time in late summer and autumn, when other flowers are no longer blooming or beginning to fade.
Prepare the planting site for your chrysanthemums by spreading a 2- to 4-inch-thick layer of organic compost or well-rotted manure onto the soil bed and mixing it into the soil. Or, spread 3 to 4 pounds of a 5-10-10 NPK formula fertilizer per 100 square feet of planting bed.
Plant the chrysanthemums at the same depth as they were planted in the nursery containers. Space the mums 1 ½ to 2 feet apart, depending on the cultivated variety's mature width.
Water your chysanthemums deeply and thoroughly once or twice each week during summer to wet the top 6 to 8 inches of soil. Water the mums only during prolonged dry spells or if your soil is sandy.
Spread a 2- to 3-inch-thick layer of organic mulch on the ground around your chrysanthemums in spring or early summer to control weeds and regulate soil moisture.
Pinch back the new shoot tips on your mums from spring until late June or early July to promote a bushier form and healthy branching. Newer cultivated varieties of chrysanthemums don't need pinching, so be sure to read the tag on the nursery container to learn about your mum types.
Apply a 4- to 6-inch-thick layer of coarse mulch around your mums to protect them during winter if your region experiences freezing temperatures. Apply the mulch immediately after the soil surface freezes and remove the excess mulch in spring.
Divide your chrysanthemums in spring, just as new growth emerges. Carefully dig up the shoots from the outer edges of the clump and replant the divisions with the growing tips just below the soil surface.