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How to Thin & Replant Day Lilies

Daylilies are popular flowering perennials that produce a variety of flower shapes and colors. Blossom colors include yellow, orange, red, purple and cream. Daylilies begin blooming in March or mid-May and typically last 4 to 7 weeks. Bright colored daylilies thrive in full sun, but the darker colors grow best in partial shade. Daylilies multiply quickly and soon form large clumps of grass-like foliage. This overcrowding negatively affects flower production. Thin and replant your daylilies as a regular form of maintenance.


Dig the entire clump of daylilies up with a shovel immediately after the flowering season has ended.

Shake off the soil from the daylily rhizomes without damaging the roots. If the soil does not want to come off, then wash the soil off with a hose.

Cut the foliage off 6 inches from the crown with a pair of sharp pruning shears. This will direct the plant’s energy into developing the roots.

Divide the clump by cutting the rhizomes with a sharp knife. Small clumps can be pulled apart.

Remove any damaged roots using the sharp knife. This will allow the healthy roots to take up all the nutrients without weakening the plant with damaged roots subject to root rot.


Dig a hole twice the size of the root mass with a small shovel. Create a small mound of soil in the center of the hole. Set the daylily on top of the mound and spread its roots out to the sides of the mound.

Fill the hole with loose soil with the daylily crown at ground level. Firm the soil around the plant with your hands.

Plant the rest of your daylilies 18 to 24 inches apart. When planted at this distance, you will not have to thin and replant your daylily flowerbed for 3 to 5 years. Your daylilies can be spaced closer together in order to fill in your flowerbed, but they will have to be thinned in 1 to 2 years.

Water the flowerbed well to help settle the soil around the newly replanted daylilies.

Spread 2 to 3 inches of mulch around the daylilies. Use wood chips, pine needles or leaves to help preserve soil moisture and to reduce weed growth.


Add 3 to 4 inches of organic material like peat moss, compost or well-rotted manure to your daylily flowerbed. This will amend the soil with slow release nutrients that the daylilies will use throughout the growing season.


Do not plant in heavy shade since this will cause thin, spindly growth and a low rate of flower production. Daylilies grow well in the light conditions under a pine tree.

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