Day lilies are very easy to grow and as one of summer’s flowering delights they deserve to be more widely grown. These perennial plants are native to the temperate areas of Japan, Siberia, China and Eurasia. They are also known by their Latin name of Hemerocallis.
There is a huge number of day lily varieties available in a wide range of sizes and colours. The natural form of the day lily flower is trumpet shaped but it also comes in other forms. These include spider shaped, circular, star shaped, flat and ruffled. There is a day lily for just about any garden situation except for deep shade and waterlogged ground.
Some Day Lily Species
There are 15 known day lily species but only a few of these are grown in gardens today. The day lily species, Hemerocallis minor, has graceful grass-like foliage and vivid yellow flowers. It provides the garden with dense clumps of sweetly perfumed ground cover plants.
The species Hemerocallis fulva ‘Kwanso’ has star shaped, rusty red flowers and Hemerocallis liloasphodelus AGM is clump forming with delightful yellow flowers. Hemerocallis dumortieri is late spring flowering with light yellow flowers and dark bud from May into June.
Daylilies readily hybridize and the modern day lily owes much to the work of Dr Arlow Burdette Stout. He spent over 40 years at New York Botanical Gardens hybridizing and growing day lilies. Stout is responsible for introducing about 100 day lily cultivars. He published the definite work on these plants, titled simply Daylilies. see it here
There are many other books on growing daylilies available. You can see a selection here
Tough and Easy to Grow Garden Plants
Day lilies are remarkably tough and resilient plants and survive in a wide range of garden situations. This makes the day lily the ideal summer plant. With careful selection you can have daylilies flowering in your garden from late spring well into the autumn.
When choosing which daylilies to grow, it’s important to remember that many of the evergreen and semi-evergreen varieties come from the southern United States. This means they may not be fully hardy in more northerly areas or in the UK. However these make ideal pot plants.
Growing day lilies in pots, particularly the less hardy cultivars, is easy and means you can bring them inside for the winter where they need very little attention other than the occasional water to stop them drying out completely. Divide and repot if necessary in spring ready for the coming summer.
Where to Plant Your Day lilies
Daylilies tolerate a wide range of garden conditions and will flower in less than ideal situations. However, you will get the best from them if you provide them with good growing conditions. Daylilies are generally sun-lovers and will flower better if they get at least six hours of sun a day during the growing season. They will still flower in part-shade and some darker coloured varieties actually do better in partial shade, particularly in hotter and drier areas.
Daylilies will grow in most types of soil including sand and heavy clay and are not too fussy about the soil pH. However they will do better if you can add plenty of garden compost at planting time to less than ideal soil types.
Daylilies also prefer good drainage and will not thrive in soggy, waterlogged soils. Adding lots of sand or grit to heavy soils should improve the drainage in problem areas. Avoid planting your daylilies close to shrubs or trees. Not only will they shade out the daylilies but they will also compete for water and nutrients.
When and How to Plant Your Daylilies
Spring or autumn is the best time to plant daylilies. For spring planting wait until all danger of frost has passed and the soil is easy to work. Add lots of organic material, such as garden compost or well rotted manure to the soil before planting. This will get your new plants off to a flying start.
Carry out any autumn planting well before frosts and cold weather are due in your area. This will allow the plants to make some roots before winter arrives. Avoid planting into very wet soil. It’s better to wait for the soil to become workable or to plant in pots if this is not possible. After planting cover with a good layer of mulch, such as garden compost.
Daylily plants come in a variety of sizes. As a general rule, miniature and small flowered varieties can be spaced between 40 and 60 cm (16 – 24 inches). Larger flowered varieties can be spaced at 45 to 75 cm (18 to 30 inches). Some varieties will increase very quickly and become crowded if you plant them too close together. If this happens and you notice a decrease in flowers then it’s time to divide them.
How to Care for Your Day lilies
Daylilies need plenty of water during the growing and flowering season. If you want lots of flowers and larger blooms make sure your plants get enough water. If there is a dry period then water every 2-3 days giving them a long soak rather than just a sprinkle. Daylilies can withstand drought conditions but there will be less flowers and they will be smaller.
Daylilies will benefit from a good feed. Feed established plants in spring just as new growth gets going. For new plants or newly divided clumps, wait a few weeks for them to get established before feeding. Use a good quality organic balanced fertiliser for feeding you plants.
Adding a mulch of organic material to day lilies improves your soil, helps retains moisture and discourages weeds. It can also help keep soil cool in the summer. Use whatever material is available in your area. Garden compost, composted bark and wood chips make good mulches.
Once established Day lilies are good at keeping down weeds. Good weed-control methods in an organic garden are mulching, hand weeding or hoeing. The best control is not to let weeds flower and seed and to keep your soil covered with plants so that weeds are unable to germinate.
Lift and divide mature clumps of daylilies approximately every three years. This keeps them flowering well and helps promote vigorous new growth. Do this immediately after flowering or in early spring as growth gets started. Don’t forget to replenish the soil with fresh compost if you are replanting in the same area. Once new growth is established keep the divisions well watered and mulched.
Dealing with Pest and Diseases
Fortunately daylilies are not very susceptible to pests and diseases. The most common pests are slugs and snails, aphids, spider mites and thrips. These pests may cause some damage to the buds and leaves. But if you plants are healthy and growing well they are unlikely to suffer permanent damage.
Clumps of growing day lilies often attract slugs and snails and these can be a problem to young leaves and flowers. Regularly inspect the day lily clumps and destroy any slugs and snails before their numbers build up.
In yellow flowered varieties of day lilies the Hemerocallis gall midge can prevent flowering and cause bud distortion. Remove infected buds by hand and destroy. The most serious disease, particularly in the southern United States, is Hemerocallis rust. Always buy your plants from a reputable source and if you suspect your plant has rust then remove the infected leaves and burn them. Don’t compost diseased leaves. If the disease is serious then destroy the whole plant.
Some Popular Day Lily Varieties
- Chicago Sunrise has golden yellow flowers and is an evergreen perennial.
- Janice Brown is unusual in that it has a light pink flower and a rosy pink centre. It is very free flowering.
- Pandora’s Box is a beauty with large cream flowers and a purple eye.
- Stella de Oro flowers from June to August. It’s low growing and ideal for the front of a border and has masses of golden yellow trumpet shaped flowers. One of the best.
- Lime Frost is one of the best of the white flowered varieties.
- Lily Luxury Lace flowers from July through August. It’s flowers are peachy with a faint lavender tint.
- Golden Chimes AGM gives a massed display of small bronzy yellow flowers during July and August.
- Golden Zebra has striking yellow variegated foliage and exotic sunshine yellow flowers. It likes full sun and is long flowering. Ideal for pots and containers.
There are many more varieties available every year. Look out for ones that have won awards such as AGM (Award of Garden Merit) or are recommended by the Royal Horticultural Society (RHS) and the American Hemerocallis Society.