Daylilies (Hemerocallis spp.), perennial flowers valued for their attractive form and ease of care, feature graceful, arching leaves that surround stalks of trumpet-shaped blooms. Flowers appear in a variety of colors from pastel shades to rich, dark reds and purples. Individual blossoms only last a single day, hence the plant's common name. Daylilies bloom prolifically, however, so you'll rarely experience a lack of flowers. According to the University of Rhode Island, established daylily plants may bloom continuously for 30 to 40 days during the spring or summer, and many varieties have more than one blooming period.
Plant daylilies during spring after all danger of frost has passed. Select a location that consists of well-drained, moist, fertile soil and receives full sunlight throughout the year for optimal growth. Spread a 2-inch layer of organic compost over the soil and cultivate to a depth of 12 to 14 inches using a garden tiller.
Dig a hole in the soil slightly deeper and about twice as wide as the plant's root ball. Place the roots in the hole so the plant's crown rests no more than 1 inch below the surface of the soil. Cover with soil and water lightly to collapse any air pockets. Space daylilies 18 to 24 inches apart.
Apply a 3-inch layer of mulch to the ground surrounding the plant to deter weeds, increase moisture retention and insulate the soil. Start the mulch about 3 inches from the plant's crown to reduce the risk of disease caused by inadequate air circulation.
Water daylilies once per week during the first two months of growth to help establish the planting. Reduce watering frequency to once every 10 to 14 days thereafter. Soak the soil to a depth of at least 6 inches each time to ensure the roots absorb plenty of water.
Feed daylilies twice per year, once during early spring and again in midsummer, using a balanced slow-release fertilizer. Water lightly after applying the fertilizer to release it into the soil and prevent root burn. Follow the manufacturer's dosage instructions for the best results.
Remove any rotten, damaged or diseased foliage during winter, the daylily's dormant period, to improve health and appearance. Remove spent flowers whenever possible to help conserve nutrients and encourage additional flower formation. Cut flower stalks back to the ground after all flowering has ended.