Daylilies are a hardy lot and gardeners love them for their versatility and prolific growth. They are drought-resistant perennials that require little fertilizer and thrive in full sun or partial shade. The best time to move daylilies is in fall as they enter dormancy or in the spring as the first fans begin to rise. Given some special care, though, all but the most fragile hybrids can make successful summer moves.
Know Your Subject
Daylilies are sturdy plants that can survive division and transplanting almost anytime during the growing season. The rainbow of colors and variety of sizes and bloom character we take for granted today are all descended from a few Asian originals that traveled first through Asia Minor and Europe to the New World but whose potential was realized by A.B. Stout, the American pioneer in hybridization. Original tawny, lemon and fulva varieties can be transplanted any time during the season; in fact, any roots left behind may put forth new plants. Hybrids, depending on their character, may need more pampering. Daylilies are grown all over the world and grow in all 50 U.S. states. It will take more than a little hot summer weather to destroy them.
You don’t like working in the heat of summer and neither do your daylilies. Do summer transplanting during the coolest parts of the day—early morning or late evening—to conserve moisture and reduce stress. Cut leaves back so that fans stand only 6 to 8 inches tall; leaves will keep growing and new ones will grow from the inside to hide the old leaves. One of the best reasons to avoid summer transplants is that you will undoubtedly lose this summer’s blooms, although very late bloomers may surprise with a few scapes. If you are moving a daylily from a shady home to a sunny one, try to shade it for a few days. Remove shading gradually to acclimate the plant to a new environment. Daylilies don’t droop when transplanted like more delicate plants but they do definitely perk up when their roots finally "take hold." Until then, water them deeply early in the mornings so that water soaks in to the cool ground rather than evaporates into the heat of the day.
The Big Move
Dig daylilies with a garden fork rather than a spade to minimize root trauma and dig under to lift clumps out of the ground. Pruning roots may stimulate them in cooler weather but it tends to shock them in hot weather. Keep plants in the shade while digging holes for new homes; use tepid water to clean roots and keep them moist. Make holes about one and a half times as large as the root mass and line the hole with a mixture of equal parts garden soil and compost or humus. Save the manure for spring or fall transplanting. Plant clumps by spreading roots over a hill of the amended soil in the bottom of the hole and fill so the crown sits where it did in the plant’s previous setting—about an inch below the surface. If soil is hot and dry, water roots with a sprinkling can before filling the hole to keep them moist. Given a little extra attention, your daylilies should settle in and start putting up new leaf growth within a week.