In the deep South, early Spring or early Fall are the most desirable planting times. Daylilies that have been shipped are more susceptible to adverse planting conditions or weather changes. Most freshly dug, undivided plants can be planted safely anytime throughout the growing season. Dividing Plants - Divide vigorous plants every four to five years. If you wait longer, the vigor of the clump may be reduced because of competition.
Considerable force is usually necessary to pull old clumps apart.
After the clump has been dug, cut or pry it into several pieces. Use a sharp knife, shovel, screwdriver or similar tool. Very important - cut the leaves back to about 6 inches. This will help your plant retain moisture. Where to Plant Sun or Shade - Most daylilies bloom best in full sun.