Daylilies enjoy a well-deserved reputation for being easy to grow perennial. They can be grown throughout the lower 48 states. Insect pests and disease are minor issues for daylilies.
Plant in full to half day sun, some afternoon shade will help retain bloom color. Do not plant close to bushes or trees with large root systems.
A well-drained soil rich in organic material with a pH between 6 and 7 is recommended. Amend soils with compost, peat, good top soil, a little manure, and / or other available organic material. Mix the added materials with a garden fork to the depth of the fork. Spending time and money on your soil is always a good investment.
During spring growth, one to two inches of rain or water per week is sufficient to produce blooms on established plants. Conserve water usage with an organic soil and / or applying several inches of a composted material, pine needle or bark mulch.
Use a time release fertilizer with micronutrients in the fall and spring when blooms begin. A handful per plant, spread around the base, is usually enough. A composted mulch is a form of slow release fertilizer which also conserves water, cools the soil, and reduces the number of weeds.
Daylily fans may increase in number of fans by two to four times each year. After a few years a clump will have formed. Fall is the best time to dig up, divide and increase your daylilies. When a clump grows in size to where it has over a dozen fans, the plant can be divided. A clump with dry soil is easier to handle than if the soil is moist. Dig it up using a garden fork or shovel. Trim half to two thirds of the foliage back, remove as much soil as possible and pull, twist, pry or if need be cut the clump using a knife or shovel. Create individual plants of one to three fans with good root systems. Remove old or dead foliage and clean the plant up. If the original plant was large then allow at least 18 to 20 inches between plants, 15 to 17 inches for medium size plants and 12 to 14 inches for small size plants.
When planting daylilies, dig a hole the width of the roots (when spread out) and about 8 to 12 inches deep. Mix a handful of time release fertilizer into the soil. In the center of the hole, make a mound of soil so that the top of the mound is almost even with the height of the bed. Place the crown (where the roots and green leaves meet) on top of the mound letting the roots drape over the mound. Cover the roots with soil, and pat the soil down around the plant to reduce air pockets. Water thoroughly to further reduce air pockets. Mulch with composted material, pine bark or pine needles up to several inches deep, but keep mulch away from crown.
Daylilies can spend weeks out of the ground and recover nicely once planted. Upon receipt of plants, plant as soon as possible. If planting must be delayed, store the plants in a cool shady location or lay the plants in a row on their side in a shady location, and cover the roots with soil until you can plant them. If necessary, soak the roots in water for 15 minutes to an hour; allow foliage to dry prior to storing.
The leaves on daylilies turn yellow and brown for a variety of reasons: because they are not happy with their growing conditions, fertilizing, temperatures, watering, because they have mites, or because they need to develop a new set of leaves and drop the old ones. With the exception of daylily rust, healthy daylilies resist diseases, which is one of the main reasons we grow them.