DAYLILY CULTIVATION

BEGINNINGS: Modern daylilies have evolved after years of thoughtful hybridizing by many different growers beginning with species plants collected from China and Japan. The common "roadside" daylily (Hemerocallis fulva) and the Lemon Daylily (Hemerocallis flava) are two known species reportedly brought to North America by early settlers emigrating from Europe. Many of today's daylilies come in a variety of shapes and sizes with clearer colors in nearly every color except pure white and pure blue.

The daylily is not a true lily even though it is a member of the Lily family. Hemerocallis is a botanical name derived from two Greek words that represent "beauty and day" or beauty for a day. Most daylily blooms last just for one day, opening in early morning and remaining open throughout the afternoon into early evening. There are exceptions. Usually, several flower buds form on each plant in various stages allowing for a succession of bloom for periods from a few to several weeks.

In upstate New York, blooming can begin as early as mid-June for extra early varieties with a main season peak bloom occurring in mid-July. Late varieties extend the bloom period from early August with a few lasting into frost. In the south, many daylilies have what is called a rebloom cycle where the plant sends up new scapes after resting for a short period. In the north this is not as common. Rebloom scapes may appear but most without sufficient time to bloom before frost. Experience will determine which scapes have a chance to rebloom and which ones should be cut close to the crown to save the plant's energies.

WHERE TO PLANT: Daylilies prefer full sun but will tolerate some shade. If full sun is not available, it is best to place them so that they will receive at least six hours of full sun each day. The lighter colors, light yellows and pinks, need more sun to bring out their colorings. Purples and reds may benefit from afternoon shade on hot summer days. Daylilies should not be planted near large trees where root competition for available nutrients may hinder their development.

Soil should be relatively well drained to eliminate standing water. This is especially true in early spring as winter's snow thaws. Although daylilies can tolerate much water, and need copious amounts to perform well, their crowns should be kept above standing water levels. Planting in a slight mound or in raised beds will help eliminate this problem.

Daylilies planted close to warm foundations and those with protected southern exposures should be well mulched in early winter. This will help protect them from starting too early and becoming susceptible to severe frost damage.

WHEN TO PLANT: Daylilies should be planted in their permanent location after the last date for spring frost. They do not like to be set back. If new plants arrive early and are planted in the garden they should be protected from late spring frost. If it is not possible to get them in the ground within a day or two of arrival, plants can be held in damp sand or moist potting medium.

Spring planting is preferable as it gives the new plant time to develop a strong root system to carry it through the winter. If it is necessary to plant in fall, put it in the ground at least six weeks before killing frost. Then, after a killing frost, mulch it well. Fall planting of southern grown plants is risky in northern climates.

Avoid if possible planting in July through early August. High temperature produces stress while high humidity and high temperature can cause conditions for disease. If necessary to plant during summer's peak, a simple protective shading device can be made by pushing four stakes in the ground around the plant and placing a brown paper grocery bag upside down over the stakes. Leave an ample air space at the bottom of the bag for circulation.

The Green Thumb-PLANTING: Newly arrived bare root plants can be soaked in a dilute (1/4) solution of liquid fertilizer. This should be for a few hours but can be over night if need be. Shipping tends to dehydrate the plants. Remove any dead roots. The foliage should be cut back to about 6 inches above the crown to reduce the transpiration loss. Extra long roots can also be cut back to about six or eight inches from the crown without hurting the plant. It is better to trim long roots then to try to curl them around the planting hole.

Work the soil to a depth of at least one-foot. Compost or other soil building amendments can be added. The soil should be loose allowing for good aeration, water percolation, and rootlet formation. The planting hole should be wider than the root spread so the roots will not be crammed into the hole.

Mound the soil in the hole so that the crown will be just below the top surface of the mound and slightly above the surrounding surfaces. This will keep the crown out of standing water. Remember that the soil in the hole will settle some so make the mound a little higher to compensate for settling. Cover the roots and compress lightly to remove any air pockets. Water liberally to settle the plant in. After the water has receded, finish filling in the hole. Remember to label the plant.

Clay soils and compacted soils will limit the root spread of the plant. This results in the cramping of new crown development that will decrease overall plant performance. Amending these soils with good compost or leaf mold, for example, will allow the roots and crown development to spread out more. The plant will increase faster and be much easier to divide and will not need to be divided as often.

Space daylilies at least 18 to 24 inches apart. This allows ample room for growth without crowding. It may look sparse but in a year or two the reason for this spacing will become apparent. Try to leave a daylily undisturbed for at least three years.

WINTER PROTECTION: We like to leave the frost-killed foliage in place. It gives a small amount of protection to the crowns. In addition, winter mulch plants with a light covering of wheat straw, pine needles or similar mulch. The mulch helps to reduce the freeze- thaw- freeze cycle damage and frost heaving. In early spring, the more hardy plants will begin to grow right up through the light mulch while the less hardy plants still receive some protection from spring frost. As spring approaches, the mulch can be pulled back from the more tender plants on warm days and pushed back over the plants during freezing nights.

Some people recommend removing the die back foliage in fall. They believe it removes a wintering over hiding place for harmful pests. If a given garden is known to have such pests, then this practice may be worth considering. It does give the winter garden a neater appearance.

DIVIDING: A daylily clump may not need to be divided before 3 to 5 years at the earliest. Decreased bloom is one indicator for dividing although there may climatic conditions that also can influence the plant's performance. A freshly dug daylily should have its foliage cut back to about six to eight inches above the crown. The general practice is to cut it in the shape of an inverted "V". The roots should be thoroughly washed clean with a garden hose. This allows better inspection and easier separation of the crowns.

The divisions can be single, double, or multiple fans depending upon the whims of the gardener or how the original clump best comes apart. Compacted crowns are difficult to divide. They are best cut apart with a sharp knife. Large compacted crowns can be forced apart with the point of a well-placed shovel and a heavy foot. Each fan should have its own collection of roots. Double fan divisions will clump up much faster than single fan divisions.

Some gardeners air dry the cut crowns before planting. Others sprinkle fungicides or a rooting hormone compound on the cut surface. We have found little need for disease protection in our cool climate. But if divisions are made in hot humid weather some sort of disease protection may be advisable.

WATERING: Daylilies thrive with ample watering. An inch of rainfall per week is considered the minimum. Without sufficient watering, bloom production will diminish. Water is needed most in spring and summer when growth is rapid and blooms are being produced.

As with most other plants, watering should be done so as to be sure it reaches clear through the root zone of at least eight to ten inches deep. Clay soils tend to retain water so they do not need to be watered as often as sandy soils. Clay soils should never be allowed to become completely dry. If overhead sprinklers are used, they are best applied during the late afternoon or evening so as not to damage open blooms.

FERTILIZING: Daylilies thrive in a wide range soil pH with approximately 6.5 being the optimum. It is best to have the local Master Gardeners check your soil pH for you at your Cooperative Extension office before making any attempt to adjust your soil's pH. If adjustments are needed, they can best advise you how to go about it.

Established plants will benefit from a spring application of a good fertilizer such as 5-10-5 or 5-10-10 following the manufacture's instructions as to rates printed on the package. Older and larger established clumps may require a little more fertilizer due to soil depletion. New plantings should not receive more than a very dilute (1/4 to 1/2) fertilizer until they are established. Foliar applied fertilizers are ideal for daylilies.

Gardeners should avoid high nitrogen fertilizer and late summer applications as they may lead to decreased bloom and lack of winter hardiness respectfully. Some commercial growers do use high nitrogen fertilizer in spring to force the plant to increase fan development. These growers are willing to sacrifice flowering and scape strength for vigorous foliage growth and fan development for future divisions.

Complied by Tom Rood, past American Hemerocallis Society Region 4 Vice President, Publicity Director/Editor, Master Gardener- Yates County Cornell Cooperative Extension, founder FINGER LAKES DAYLILY SOCIETY.

Acknowledgments: Leslie Hegeman, Past President, Long Island Daylily Society. Nassau County Cornell Cooperative Extension. Daylilies-The Beginner's Handbook 1991 Revised edition. American Hemerocallis Society.

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Updated: February 15, 2004