Skip to Main Content

LuEsther T. Mertz Library
Plant & Research Guides

Library Home Plant Help Research Support All Guides

Library Home Plant Help Research Support All Guides

Divine Daylilies: Home

Hemerocallis 'Outrageous'; Photo by Michelle Longo
Hemerocallis 'Outrageous' at NYBG; photo by Michelle Longo

Daylilies are an extremely popular perennial. They are fairly low-maintenance and make wonderful plant partners for both ornamental shrubs and perennials in a mixed border. They are adaptable plants, flourishing in hot and cold climates and tolerating drought. Daylilies are overall good performers. Hybridizers are coming out with dazzling cultivars in every size, shape and color you can imagine.

The Latin name, Hemerocallis, means beauty for a day. The individual flowers, as the name suggests, last for only one day. The flowers are positioned on scapes--tall, leafless stalks that rise from several inches to 3 feet above the lush, strap-like foliage. The branched scapes produce from 10 to 50 buds each, ensuring a long flowering season (6 weeks on average).

Depending on the cultivar, flowers appear from late spring into October. They are classified as early (E), middle (M), or late (L) and reblooming (RE), with several variations in between. Rebloomers can be "bud builders" which produce new buds throughout the season, such as the popular 'Stella de Oro', or cultivars that flower once, take a small vacation, and then rebloom later in the season.

Basic Daylily Care

  • Daylilies prefer 6 to 8 hours of sunlight but will tolerate partial shade. Some daylilies, particularly the darker shades of red and purple and those with pastel-colored flowers, fade in the heat of the afternoon sun. Position them in afternoon shade to retain their color and beauty.
  • Most daylilies prefer moisture, but they tolerate dry conditions as well. They grow well in heavy loam to light sandy soil. Many of the species and older cultivars are tough. You can toss them in the ground and watch them grow.
  • Newer cultivars tend to require more pampering. Amend your planting site with compost and fertilize with a well-balanced granular fertilizer in the spring.
  • Add a mulch of shredded leaves, compost or composted bark around the base of the plants to retain moisture levels in the soil and suppress weeds. Do not cover the crown (juncture where roots and foliage meet) of the plant with mulch.
  • Supplemental watering before and during flowering time will help increase the vigor of the plant and the number of flowers.
  • Space daylilies 1½ to 3 feet apart, depending on the size and vigor of the cultivar. Many cultivars are fast growers and will need space to expand.
  • Daylilies should be planted and divided in early spring or early autumn. Plant daylilies so that the crown is slightly below soil level.
Daylilies on display in the border at NYBG
Daylilies on display in the border at NYBG


Deadheading daylilies is important. Snap the dead flower off at the base of the flower (where it joins the scape). Make sure that you snap off the entire flower (not just the petals); otherwise a seed head will form. If too many seed heads form, the plant's energy will be channeled into seed production, resulting in a weakened plant with poor flowering the following year. Once all of the flowers have bloomed, cut the scape down to the basal foliage (base of the plant).

Some small-flowered cultivars are self-cleaning and require less deadheading. Rebloomers should be deadheaded to encourage repeat flowering and showy, large cultivars should be deadheaded for aesthetic reasons. Some purple or red flowers stain your hands when you deadhead them.


After the plant has flowered, it is common for some of the foliage to start to die back. Either pull the yellowing foliage off by hand or cut with a pair of pruners. If the foliage starts to look too tattered, you can cut the entire plant down to several inches from the ground (4 to 6 inches). The foliage will then rejuvenate within a month. Remember to give the plant supplemental water to encourage the new growth. Don't cut the entire plant back every year because you'll weaken the plant.

Some daylilies are evergreen, some semi-evergreen and others dormant in the winter. Evergreen daylilies are best adapted to warmer climates. In the New York area, most daylilies go dormant. You can either clean up the dead foliage in late fall or wait until early spring.

Dividing Daylilies

Most daylilies need to be divided every 4 to 10 years, depending on the vigor of the cultivar. Reblooming daylilies tend to be more vigorous and should be divided every 2 to 3 years. To divide, lift the clump with a fork and shake or wash off excess soil. Divide with a sharp knife or spade. If the clump is very large, try the double-fork method. Make sure that the new divisions have 1 to 4 fans of foliage. The larger the division, the faster it will rebloom. Amend your soil with compost when you replant.

Hemerocallis 'Rajah' at NYBG
Hemerocallis 'Rajah' at NYBG

Pests and Diseases

Daylilies are fairly disease and pest resistant, making them good candidates for a low-maintenance garden. They are sometimes attacked by aphids and thrips; neither will kill the plant, but they may disfigure the flowers. The easiest remedy is to spray the plants with water or soapy water.

Daylilies benefit from supplemental water during hot summers. Overhead watering (and rain) may spot the flowers, but since each lasts only a day it won't destroy the beauty of the plant. Daylilies can also suffer from leaf streak, a fungal disease that causes discoloration of the leaves. Simply remove damaged leaves.

Along Daylily Walk at NYBG; photo by Maria Perez
Along Daylily Walk at NYBG; photo by Maria Perez

Ask a Plant Expert

Contact Us

with your plant questions by email

Find a Plant at NYBG

Find a Plant at NYBG

Map of NYBG

Noteworthy Books on Daylilies