Daylilies are native to Asia but were introduced to Europe in the early days of the Silk Road, possibly as long ago as the second century. From there daylilies traveled with immigrants to North America where they became ubiquitous in early gardens. There was a resurgence in popularity in the 1920’s when the cultivar Hyperion was released. The new cultivar produces a profusion of long lasting bright yellow flowers that have a sweet scent. After nearly 100 years, this cultivar is still available today. The modern era of daylilies was introduced by Dr. Arlow Stout while he was working at the New York Botanical Garden from 1911-1948. Dr. Stout is considered the father of modern daylily breeding and introduced over 100 new hybrid cultivars with his cross breeding experiments. While all daylilies are in the Hemerocallis genus, there are at least 16 different species. Through breeding, however, there are now over 90,000 named cultivars according to the American Daylily Society. Most of these cultivars are descendants of just two daylily species; Hemerocallis fulva and Hemerocallis lilioasphodelus (flava).
The daylily is a member of the lily family, and its Latin name Hemerocallis translates to “beauty for a day” because the flowers typically open for only one day. However, what they lack in longevity, they make up for in numbers, with a quick succession of blooms throughout the summer and into the fall.
Daylily flowers are trumpet-shaped, with double and single versions that range in size from 2 to 6 inches. Originally found only in burgundy, yellow and orange, these days there are many new colors from which to choose, including gorgeous peach, creamy whites, purples, lavender, rose and even pinks. There are multi-colored selections as well.
Daylilies grow in thick clumps with their dark green, blade shaped leaves emerging in a profusion of arches from the soil. During the blooming season they will produce long scapes (flower stalks) with multiple blooms each. The scapes of most cultivars range in height from 12 inches to 5 feet. Modern daylily cultivars commonly produce 15 or more flowers per scape.
The root system of daylilies can form a dense matt and can be useful to help control erosion. Be careful planting daylilies over the roots of trees and shrubs because the extensive root system of the daylilies will out compete them for water and nutrients.
Daylilies reproduce themselves sexually through pollination of the flowers or asexually by creating new plants from underground stolons. Asexual reproduction will make plants that are genetically identical to the parent whereas sexual reproduction will result in plants that can appear similar to or wildly different from the parent flowers. It is through sexual reproduction that new varieties are developed. Plants are easily propagated by dividing clumps, or they can be grown from seeds.
Site and Soil:
Daylilies are adaptable to different light conditions but will flower best if they receive at least 6 hours of direct sun per day. Light shadeduring the hottest part of the day will help the flowers last longer. They are tough plants that can grow in a wide range of soil types but prefer slightly acidic soil with plenty of organic material. The soil should also be relatively well-draining if you want your daylilies to grow year after year. Planting in mounds, raised beds or planters will help if the soil is too wet.
Planting and Dividing:
The best time to plant and divide daylilies is in the early spring and fall after the flowers have stopped. Dividing daylilies-Daylily clumps can be divided every three to five years. Dig up the entire clump with a spade. Carefully pull the clump apart by hand or divide the clump into sections with a large knife or spade. Each division should consist of 2 or 3 fans of leaves and a good root system. You can replant some in the same area and find a new home for the offspring in another part of your landscape, with friends and neighbors or put them in your compost pile.
1. Till the soil deeply before planting or use a garden fork to break up the soil.
2. Add compost and work it in to increase organic matter.
3. Take a soil test. The result will tell you the nutrients that are available in the soil as well as the soil pH.
4. Incorporate fertilizer according to the soil test recommendations or use a complete slow release fertilizer. You may also add soil amendments to change the soil pH at this time.
5. Dig a hole wide enough for the roots to spread out without bending or crowding them.
6. Place the plant in the soil so the crown (the portion where the stem and root meets) is one inch below the soil level. If needed, add soil back into the hole to lift the plant up.
7. Once the plant is at the right level, back-fill with the garden soil, lightly packing it down around the plant.
8. Water until the soil around the plant is thoroughly saturated. Not only does watering hydrate the plant, but it also settles the soil around the roots eliminating large air pockets.
How to care for daylilies:
Daylilies are hardy plants that require very little care.
In early spring, cut back and remove the dead and damaged from the previous year's growth and pull any weeds.
Apply one application of fertilizer in the spring according to the soil test results or use a complete fertilizer such as 10-10-10. Be careful, too much fertilizer will lead to heavy foliage growth with few flowers.
A spring application of compost around the base of the plants is beneficial each year.
Add mulch to help minimize weeding and help keep the soil cool and moist.
Keep soil moist — 1 inch of water weekly is ideal, more frequent watering may be necessary in sandy soils or for plants grown in containers or raised beds. Daylilies tolerate drought, but they perform best when the soil is kept moist.
Remove dead flowers after bloom to prevent seed production. This is called "deadheading." Plants that produce seeds are likely to have fewer flowers the following year.
Overcrowding of plants can cause a decline in flower production, so thin the plants every three to five years in late fall or after plants have finished blooming. You can replant in other areas or share them with friends.
Insect control measures are usually not necessary. Aphids, spider mites and thrips sometimes feed on the flower buds. These pests can be controlled with insecticidal soaps or a repeated strong spray of water.
One disease problem is daylily rust, identified by orange powder spots on the undersides of leaves. Infected plants should be cut back to an inch or less and treated repeatedly with labeled fungicides. Foliage from infected plants should be removed and destroyed or you may choose to remove the infected plants altogether and replace with a variety less susceptible to the disease. Fungicides recommended (for prevention more than control) are Systhane, Banner Maxx, Contrast and Heritage. All are systemic materials. Others to consider are Strike (systemic) and Dithane (protectant/contact). Most broad-spectrum contact and systemic fungicides may be somewhat effective and may be useful in combination; however, effectiveness is limited.
Varieties less susceptible to the disease include Little Business, Mini Pearl, Butterscotch Ruffles, Mac the Knife, Yangtze and Holy Spirit. Local nurseries can also help identify less susceptible varieties.
Selecting your Daylily:
With so many varieties available on the market it can be difficult to pick the plant that is right for you. Here are some things to think about when selecting daylilies for your garden.
Know your zone-Varieties of daylilies are “regional performers,” which means they grow well only in certain parts of the country, usually over three hardiness zones. Select varieties that are described as or proven to work in your zone.
Bloom time-Daylilies have early, mid and late-season bloom times. Furthermore, some varieties have the ability to rebloom meaning they can produce flowers at least twice per year. With our long season, many varieties can be encouraged to produce new blooms by removing faded flowers. Select varieties that will bloom at your desired time or select several varieties with different bloom times to prolong the flowering season.
The size of individual plants can range from less than a foot to over 4 feet tall. This is just the leaves. The flower bearing scapes can be even taller.
Flower color, shape and size:
As you can see from figure 1 on the previous page daylily flowers come in a large variety of shapes and styles. They also range in size from 2 to six inches and come in nearly every color of the rainbow (except blue) and combinations of colors.
Ultimately you should pick what you like while keeping the criteria above in mind.
Currently I do not have any daylilies in my home garden but I probably will soon. If you have not noticed them already, take a look around you and you will likely start to see daylilies all around you. As you are looking, think about which ones you like and which you think would look nice at your home.