Do any insects or diseases affect daylilies?
Though daylilies are generally very low maintenance and are not bothered much by pests or diseases, occasional problems may occur. Under certain conditions, thrips and mites may feed on daylilies. Many people simply tolerate the occasional damage these insects do to daylily foliage and blossoms. Others choose to apply pesticides appropriately chosen. Orthene is effective in controlling thrips. Mites usually infest daylilies that are drought-stressed. Keeping your daylilies well-watered will usually keep mites at bay. Avoid using Kelthane, a common miticide on daylilies, as serious foliage damage to the daylilies will occur.
Daylilies also are occasionally infested with foliage diseases. Two of the most common are leaf streak and bacterial leaf spot. Commonly available fungicides such as Dithane or Daconil are useful in controlling such diseases.
None of these problems is so damaging to daylilies that special care is necessary. In most cases, even if you do nothing, your daylilies will perform satisfactorily.
Do daylilies come in different heights?
Daylilies come in a wide range of heights from dwarfs that are under 12 inches tall to a few that approach 6 feet tall. As you are selecting daylilies for your particular plantings, pay attention to the plant height which is noted in the catalog description. Such height information applies to the height of the bloom scape at maturity, not foliage height. Height information is also approximate, due to the fact that growing conditions in different areas of the country result in the same cultivar reaching somewhat variable heights.
Short daylilies are useful as edging plants. They work particularly well if a single cultivar is planted en masse. Single clumps of short cultivars are also showy in rock gardens, near mailbox bases, and scattered near the front of mixed borders. Although it is not classified as a particularly short daylily, 'Mardi Gras Parade' makes a wonderful plant for edging walkways. It is a profuse bloomer with narrow arching foliage and uniquely presents many of its blossoms at or near the same height.
Daylilies of medium heighth can serve well in just about any setting. Always keep height in mind when you are designing a planting. For example, you would not want a short daylily placed behind taller perennials where it could not be seen. Also keep in mind that a daylily's height and blossom size are not necessarily correlated. Daylilies come in every size imaginable, from short plants with large flowers to tall plants with small flowers.
Use tall daylilies at the rear of planting beds. They serve as useful accents in mixed borders and go well with other tall perennials such as Phlox paniculata (cv. 'DAVID', 'EVA CULLUM', 'ROBERT POORE', and 'SHORTWOOD') and Eupatorium (Joe Pye Weed).
Do my daylilies need any special protection in the winter?
Established daylilies require no winter protection whatsoever. Most growers simply allow the daylily foliage to remain on the plant over the winter, where it serves as natural mulch. The partially decayed old foliage is removed at spring clean-up time. Other growers cut the daylily foliage to the soil level in the fall after freezing temperatures has killed it. They then remove and compost the foliage, leaving the clump clean and uncovered during the winter. Either approach appears to work we
Do my daylilies need to be fertilized?
Many gardening guidebooks describe daylilies as effortless perennials. Daylilies are certainly easy to grow, but they will perform better if given periodic care. Fertilizing your daylilies twice a year, once in early spring just as the plants resume growth, and again after they have finished blooming, will help them look their best. Low nitrogen fertilizers such as 5-10-10 or general ones such as 10-10-10 work well with daylilies. Organic fertilizers, such as animal manures, are also beneficial.
How can I keep my weeds under control?
Mulch is very effective for controlling weeds. Applying mulch around the base of the daylily clump in early spring, just as the plants are resuming growth, will help suppress weed growth. As the foliage matures, it helps shade the soil around the base of the clump, thus helping further to suppress weeds. Weeds can be removed quite readily from a mulch cover.
Cultivation with a scuffle hoe is also effective, although some daylily roots will inevitably be near the surface and may experience some damage. Cultivation must be systematic, because weed seeds will germinate throughout the growing season.
Preen, an herbicide widely available to retail consumers in garden outlets, works well with daylilies. Other herbicides such as Pennant, Snapshot, and Factor are also registered for use with daylilies but are typically used only by large-scale commercial growers. These specialized products are usually not available through common retail garden sources. They usually are purchased through agricultural suppliers and require both special knowledge and care in their correct application.
How deep should daylilies be planted?
Daylilies should be planted at a depth where the crown (the junction point between root and foliage) is approximately one inch below the soil line.
How do I divide a daylily clump?
The most common way gardeners increase their daylily plantings is by periodically digging up and dividing the mature clumps. Daylilies should be divided every four to five years in order to ensure best bloom performance. After many years, the plants typically have become overcrowded and their bloom quality and quantity decline.
Dividing a daylily clump is a very simple process. However, it does require some physical exertion and the appropriate tools. Most gardeners use a strong spade or spading fork to lift the mature clump. Partial lifting from both sides of the clump should loosen it from the soil. Do not worry about cutting or breaking roots. Daylilies are tough.
Once the daylily clump is out of the ground, simply use the spade to cut the clump into multiple sections, much like cutting a pie. Experience has shown that even such rough treatment that results in some crown cutting has no adverse effect on the replanted segment. The partial clump simply resumes growth when replanted, and by the following season, the clump will look just fine.
Some gardeners prefer to use a sharp knife to separate the individual plants in the clump. This is often easier if the clump is washed free of soil before taking a knife to it. Sandier soils simply fall from the clump. When dividing the individual fans, use the knife to separate the plants, not to cut them apart. Again, however, do not worry about root damage. The clump will contain a mass of tangled roots. Many of these will fall off or be cut in the process of division. This is OK. Daylilies are prolific root makers. Replanted daylilies will soon send out new major roots from the crown and small feeder roots from the fleshy stabilizing roots.
Some gardeners keep their daylilies in good condition by periodically reducing the size of the clump. This is done by slicing the clump in half with a sharp spade, removing half the clump, and adding fresh soil to the side where the partial clump was removed. When such an operation is performed in late summer, the parent clump usually recovers well to put on an acceptable display the following summer. The removed half-clump can then be divided further into plantable divisions of two to three fans each. Division down to single fans is possible if you want to obtain the maximum number of plants for replanting a large area but these single divisions may take a few years to bloom again.
Remember your gardening friends when you are dividing your daylilies and have surplus plants. Daylilies make great gifts!
How do I plant bare root daylilies?
Dig a hole about a foot deep and 12-18 inches in diameter. Mound soil up in the center of the hole. Position the daylily at the top of the soil mound so that the crown will end up about one inch below the soil surface when the hole is filled in. Spread the roots out around the mound of soil. Refill the planting hole and firm up the soil around the plant. Make sure there are no air pockets, then water well.
Daylilies should be positioned about 18 inches apart if planting for mass effect and 24-30 inches apart for specimen clumps.
Water your newly planted daylilies once a week. DO NOT water every day. Newly planted daylilies need to be encouraged to send out new roots, and they will do that in search of moisture. Newly planted daylilies rarely rot, but over-watering during times of high heat combine to create stress for the plant. When in doubt, don't kill your daylilies with kindness.
What are good companion plants for daylilies?
Spring bulbs work amazingly well in plantings that feature daylilies. Use bulbs such as daffodils, crocus, and grape hyacinths which are long-lived and do not require frequent replacement like tulips do. Daffodils come into full bloom with mature foliage just as daylilies are resuming their own growth. By the time the daffodils are finished and their foliage begins to die back, the daylilies have developed full, mature foliage which masks the daffodils' yellowing leaves.
Almost all perennials that prefer to grow in full sun or partial shade combine well with daylilies in the landscape. Some common companions include:
- Leucanthemum (Shasta Daisy)
- Echinacea (Coneflower)
- Rudbeckia (Black-Eyed Susan)
- Campanula (Bellflower)
- Phlox (Tall Garden Phlox)
More companion plants are listed on each cultivar record on this website.
What do the abbreviation codes used for daylilies stand for?
- D=Dormant Refers to the type of foliage.
- E=Early bloomer In Michigan, this means the daylily blooms in June.
- EV=Evergreen Refers to the type of foliage.
- EXT=Extended bloom The flowers remain open for at least 16 hours each.
What is a daylily?
A daylily is a perennial which is characterized by its long, narrow, strappy leaves and its flowers which each last only one day (hence the common name Daylily).
Its botanical name is Hemerocallis. Daylily is one word, not two, although even The New York Times regularly gets this wrong. These outstanding plants are now the best selling, most popular perennial in most of the United States.
Daylilies have a crown which is the intersection where the roots and foliage meet. The foliage emerges from the center of this crown in fans. A three year daylily clump may contain 10-30 individual fans, most of which will produce a bloom scape.
When the foliage matures in midsummer, the flower stalk emerges from the center of the fan. Each scape contains 10 to 40 or more buds, thus making a progression of bloom which may extend over three to four weeks. Some daylilies are repeat bloomers and others can flower all summer long, but these are exceptions.
Daylilies have a specialized root system. They are not bulbs, tubers, or corms. Instead, they have fibrous, fleshy roots of all different sizes. The larger ones may be as thick as your finger! These roots store the nutrients and water which serve as the plants' energy reserves.
Most of the work in daylily hybridizing (coming up with new cultivars) has been performed in the United States. Major advances in improving daylily quality and diversity have been made in the past 50 years.
What questions should I consider when designing with daylilies?
What are you trying to accomplish? What do you want to see as the finished result?
Are you featuring daylilies as the primary attraction? Or will daylilies serve a specific purpose in a mixed perennial planting?
Do you need prominent bloom color at a particular time in the growing season?
How much effort should be anticipated in maintaining the planting?
What colors will be featured? Will they complement one another or contrast with the color of another perennial?
Does your intended planting area contain significant features, such as a pool, fence, or stone wall?
Is the planting intended to be admired from a distance or close-up?
Are you creating a totally new planting, or are you renovating or enhancing an existing planting?
Does the landscape already provide a backdrop? Will you need daylilies of varying heights?
Is your plant acquisition budget adequate to obtain sufficient plants to achieve your intended result?
When is the best time to plant daylilies?
Daylilies may be planted at any time during the growing season when the soil is workable. Spring-planted daylilies are likely to bloom the first season, but bloom probably will be substandard. Summer and fall-planted daylilies usually perform well the following summer. Container-grown daylily purchases can be replanted at any time, even in full bloom, without much adverse affect on the plant.
Fall-planted daylilies benefit from mulching the first winter. Bark chips, ground leaves, chopped straw, and pine straw all work well.
What are the different daylily foliage types and why is foliage type important?
Daylily hybridizers and specialists typically classify daylily foliage in three categories:DORMANT
Dormant means deciduous. Dormant daylilies lose their foliage completely when frost arrives in the fall. They then remain leafless or without foliage for some period of time that is variable both by cultivar and growing region. Dormancy may be affected by day length and temperature change.
Photoperiod-sensitive dormants develop yellowish foliage and begin a gradual die-back before frost as day length shortens in the fall. Temperature-sensitive dormants remain green until freezing weather arrives, at which time they stop growth and die back. Dormant daylilies overwinter with the next year's fans as buds or buttons of new foliage on the crown below the soil line. Upon receiving the signal from Mother Nature that the time to resume growth has arrived, the new growth emerges from these buds. New foliage that appears in the spring on dormant daylilies is typically very attractive, looking very healthy and green. EVERGREEN
Evergreen actually means ever-growing or foliage-persistent. Evergreen daylilies continue growth year-round in mild climates that do not experience below-freezing weather in winter. Evergreen daylilies attempt to grow continuously in colder, northern climates, but their growth is interrupted by cold temperatures. In very cold climates, evergreen daylilies essentially halt their growth during the winter. In transitional climate zones, where the soil does not remain continuously frozen through the winter, evergreen daylilies may continue to push up new foliage on warmer days.
In northern gardens, evergreen foliage dieback is progressive with increasing cold weather. Unlike dormants, evergreens do not shed their foliage at a particular time. Each leaf on an evergreen fan tries to keep on growing. Usually only the tips of the foliage show damage of frost at first. Freeze damage subsequently causes dieback further down the leaves. Unless they are cut back to the soil line, evergreen daylilies will often show green foliage on several inches above the plant crown, even in mid-winter. While the spent foliage on dormant daylilies dries out and decays over winter, freeze-damaged evergreen foliage is often mushy and slow to dry and decay. It's not a bad idea to remove this yourself in the spring. SEMI-EVERGREEN
By definition, a semi-evergreen daylily behaves like a dormant in the north but acts like an evergreen in mild, frost-free climates. Semi-evergreens theoretically perform reasonably well in both southern and northern gardens. In reality, the semi-evergreen classification may be considerably more complex.
Semi-evergreen daylilies possess foliage that is slower to die back in the fall than the dormants. Usually, a few green shoots, 2 to 4 inches tall, remain visible even after exposed to quite severe cold. These tips may be mushy from successive freezes but, unlike the evergreen types, the main body of old foliage on semi-evergreens dies back completely. Semi-evergreens are often quicker to re-emerge in the spring than are the dormant types.
In northern regions...
- Dormant daylilies are usually totally winter-hardy in the north.
- Evergreen daylilies typically require mulching or other special winter protection to successfully survive northern winters. They are usually not suitable for open-field growing without winter protection in the north.
- Semi-evergreen daylilies fall somewhere in between the dormant and evergreen types.