Gardeners can't get enough of daylilies, and it's easy to understand why. Other flowers may be as beautiful, but no other plants are as rugged, widely adapted, or versatile. Daylilies are gorgeous and they are survivors, perfect plants for both the connoisseur and the weekend warrior. Originally from Asia, daylilies have adapted to our challenging and varied climates with all the vigor of our best native plants. They grow in all United States regions, but thrive in USDA Hardiness Zones 4 through 9.
A good daylily variety will bloom continuously for 3 to 4 weeks. By choosing varieties carefully, you can have daylilies flowering for the entire perennial season, 3 months in the North to 10 months in the South.
It's an astonishing performance, but daylilies can do even more. They grow thickly enough to choke out most weeds. They excel at holding the soil on steep slopes and other erosion-prone spots. They bask in the heat of our summers, withstand intense sunlight, and survive drought better than most garden flowers.
That's why we see the old-fashioned Hemerocallis fulva along roadsides and stream banks in many parts of the country. It's one of the few garden plants to survive when farmsteads are abandoned.
The modern daylily, with its great variety of flower forms and colors, is an American creation. When A. B. Stout started breeding daylilies at the New York Botanical Garden almost 100 years ago, there were only a handful of varieties, all of them very close to the dozen or so wild species being grown at that time. Stout crossed wild varieties, and his success inspired the daylily boom we are in the midst of today. Since 1900 about 40,000 varieties have been named in the United States; 13,000 of them are still for sale.
Basic Features of a Modern Daylily
Daylilies are categorized in several different ways. Deciduous kinds go dormant in frosty weather, evergreens can tolerate frost and grow all winter in mild regions, and there is an intermediate group called semi-evergreen. The rule of thumb is to avoid deciduous daylilies south of zone 8 and avoid evergreens north of zone 7. It's good advice, though there are a few varieties in each group that defy the rule.
Most daylilies have arching foliage that grows 18 to 24 inches tall. Some varieties have erect foliage. Some are as low as 12 inches and others reach 3 feet. Leaf color ranges from pale green to dark green with a bluish cast.
The height provided in nursery descriptions and on plant labels doesn't refer to the foliage but to the length of the flower stalk or "scape." There is no correlation between height of the plant and the length of the scape, though most hold their flowers just above the leaves. Flower scapes on the shorter varieties grow as high as 12 inches. Scapes of the tallest reach over 6 feet high.
Single daylilies have six petals. Double varieties have a second set of petals, often ruffled. Flower size ranges from 1 1/2 inches--the "miniature" varieties--to 8 or 9 inches across. The color range of daylilies has expanded to include everything but blue and pure white. Many blossoms are bi- or tri-colored. Many modern daylilies are called "tetraploids." They have twice as many chromosomes as the normal "diploid" varieties. These sturdy varieties generally have larger leaves, stalks, and flowers.
Shopping for the Best
You'll find the greatest selection of daylilies in the catalogs of mail-order specialists. Most varieties cost $3 to $10, but you'll see some selling for hundreds of dollars. Remember, paying a lot doesn't ensure quality, only rarity.
For the typical gardener, selecting from the thousands of available varieties can be daunting. Here's some simple advice: Focus on the whole plant. If there are 4,000 daylilies with yellow flowers, common sense suggests that not all will grow in the same way. Some of those yellows grow significantly faster, produce more flowers, and have more attractive foliage than others.
If you look car at the plants in a display garden or a nursery, there are clues as to how they will grow in your garden.
Number of Flowers
Where nights are very cool, daylily flowers don't open as readily in the morning. You can solve this problem by growing "nocturnals." These are varieties with flowers that open at dusk and remain open throughout the following day.
Rate of Increase
How to Use Daylilies
Daylilies are stalwarts of the perennial border, but they shine in other spots, too. Vigorous daylilies make weed- and erosion-proof ground covers. Plant them on banks and roadsides or along waterways. Use dwarf daylilies in rock gardens, in containers, or as edging for flower beds.
When planting several daylily varieties, arrange drifts of a single variety. A random mix almost always looks spotty from spring through fall. Foliage varies tremendously among cultivars. So does bloom time and the height of the flower stalks. Group at least three clumps of one variety together and you'll get both a more natural look and a stronger impact at showtime.
Planting and Care
Daylilies grow best in full sun, ideally 6 hours or more daily. However, in hot and dry climates, they benefit from some afternoon shade, as well as irrigation during bloom. Also, many of the deep reds and the paler shades hold their colors better in partial shade. In any zone, daylilies will perform reasonably well with half a day's shade -- they just won't bloom as vigorously.
Daylilies grow well in a wide range of soils. You can plant daylilies successfully almost any time the ground can be worked. The ideal time to transplant and divide is in spring as the shoots begin to emerge, or immediately after bloom. In zones 9 and 10, plant in early spring (February or March) or fall; avoid planting in midsummer. Likewise in the Southeast, don't plant during midsummer because the high temperatures and humidity may cause new plants to rot. When fall-planting in cold regions move the plants at least a month before hard frosts to allow new roots time to take hold against frost heaving.
Space plants 18 to 24 inches apart. Plant at the same height plants grew previously (the white at the base of the foliage) or slightly higher to allow for settling. Firm soil, then water.
Some cultivars can grow for 20 years without requiring division, but others may need division every second or third season. You'll know it's time when you notice flower production declining.
Many daylily varieties perform well over five hardiness zones. But a variety clearly superior in Georgia may be only average in San Diego. That's why it makes sense to buy from local daylily specialists or from mail-order specialists in your hardiness zone. For information on daylily nurseries, contact the American Hemerocallis Society (Pat Mercer, AHS Executive Secretary, Box 10, Dexter, Georgia 31019). It welcomes beginners and will send a free membership information packet that includes a source list with 118 nurseries, plus information about its 15 regional groups and 133 member display gardens, many of which have daylilies for sale. Membership is $18 annually and includes the quarterly Daylily Journal.