Hemerocallis Species - The Day Lilies

Day Lilies are commonly grown garden plants, most garden centres will stock at least a few of the many cultivars that are available. These hardy perennials have large and attractive blooms that are similar to lily flowers. They are very easy to grow, many of the forms are tolerant of almost total neglect and will still be seen thriving in a neglected garden long after most of the other cultivated perennial species have been choked out by the invading native plants. Day Lilies are actually cultivated as food crops in some countries, such as China and Japan. All parts of the plants are edible though it is the flowers that are most frequently used. Day Lilies also have a number of other uses and deserve to become a standard plant in edible and ornamental gardens.

The genus comprises about 20 species, most if not all of which can be grown outdoors in temperate climates. The common name day lily was given to the plants because, as well as resembling the true lily, the flowers of most species are very short-lived and often die within a day of opening. The plants do produce a succession of flowers, however, often for a period of a month or more. As well as the species, there are quite literally hundreds of named varieties available. These varieties often have such a long history of hybridisation that it is no longer possible to assign them to any species. So popular have they become that they have largely replaced the true species in cultivation, and nowadays you normally have to go to a specialist supplier if you want to obtain any of these original species.
 

Cultivation

Day Lilies must be some of the most easily grown perennial garden plants. They succeed in most soils, from fairly light and dry ones to heavy clays, though they are happiest in a soil that is rich and moist. They grow better and flower more freely when in a sunny position, though they will also tolerate quite a bit of shade. Whilst fewer flowers are produced on plants in the shade, each flower tends to be longer-lived. Plants prefer a neutral to slightly acid soil and will be unhappy in very acid or alkaline soils. Hardiness varies from species to species, but there are plants that are suitable even for the coldest temperate gardens.

Generally free from pests and diseases, the main problem is usually slugs and snails. These little beasts just adore the fresh new growth in late winter and spring. Most species, fortunately, are quite vigorous and will generally grow away from early damage. Plants most at risk are those that are freshly divided, or small young plants that have just been planted out.

Plants increase by forming new shoots from the roots. Most species and cultivars are quite well behaved, forming quite tight clumps of growth and not spreading too far, but some species are rather more active and their running roots will send up new growths a yard or more away from the main clump. The more vigorous of the clump forming species will grow quite happily in short grass - you can mow the grass around them, but do not mow the clump. Species with running roots will also succeed in grass, though it is impossible not to cut out some of the new growth when mowing.

Propagation

Propagation is exceedingly simple. Seed can be used but, because of the possibilities of hybridisation, you need to either obtain the seed from a known wild source or hand-pollinate plants in the garden while using some method of excluding pollinating insects from the flowers. Of course, this is only important if you want to breed a species true to type. The seed of cultivars will not usually breed true to type, the seedlings displaying a mixture of characteristics from the parents of the cultivar. Hybridisation has been widely used in order to produce new ornamental cultivars, and it does also present the opportunity to start breeding for superior edibility.

Seed is best sown in early to mid spring in a greenhouse. Use a freely draining compost and cover the seeds to twice their diameter. Germination is usually good, taking place in about 3 weeks from sowing. Prick out the seedlings into individual 3 inch pots in a fairly rich compost as soon as they are large enough to handle and then grow them on in the greenhouse for the rest of the growing season. It is often possible to plant out these seedlings in late spring of the following year but, if the plants still look small or you have a slug or snail problem in your garden, then pot them into larger pots and grow them on for another year before planting out in the late spring of the following year.

Division is very easy, and this is the only way of ensuring that named cultivars remain true. Most plants come into growth very early in the year, some species will actually start growing in the previous autumn and will already be an inch or two tall by January. The clumps are usually divided in late winter to early spring, though some growers will also do this in late summer once the plants have finished flowering, or in the autumn once growth has died down.

For maximum increase, simply dig up a clump and break off individual new shoots together with some root. These are probably best potted up so that they can be easily protected from slugs until they are growing away strongly, though you can also plant them out into the open garden. If you do not need such a rapid increase, but want to obtain large clumps quite quickly, then divide the plants into 2 - 4 pieces and replant straight away into the garden. If the clump is so tight that it is difficult to divide, then you can cut your way through with a sharp knife or even chop the root with a garden spade. Another method is to insert two forks back-to-back into the clump with the rear of their prongs touching and the handles about 1 - 2ft apart. You then bring the handles together and this levers the clump apart.

Plants can be a bit slow to settle down after division and it can be a year or more before they really get going again, though they will soon make up for the lost time. One way of dividing a clump without the need to dig it up is to gently tease away young shoots from the outside of the clump. You will normally have to excavate a small amount of soil to make sure that you get some roots with the shoots. Pot them up and then plant them out when well established, usually in mid summer. This form of division is especially easy with those species that have running roots. 

Uses

Let's look now at how they can be eaten. The flowers can be eaten raw when they are fully open, though they can be eaten at any stage from green bud to when they begin to wither. The flower buds are normally cooked, though they can also be eaten raw. They have a taste somewhat like green beans. If the flowers are harvested when fully open they make a superb and very ornamental addition to the salad bowl. You might like to pick and munch on them as you wander around the garden. The petals are quite thick, crisp and juicy with a delicate sweetness at their base due to the nectar they contain. At this stage they are also at their most nutritious, containing reasonable quantities of protein (mainly from their pollen) and carbohydrates (from the nectar) as well as good quantities of iron and vitamin A.

In the Orient they usually harvest the flowers just as they begin to wither. The flower are then dried and used as a flavouring and thickener in soups etc.

The young shoots have a pleasant sweet flavour and make an excellent cooked vegetable, though older shoots quickly become tough and fibrous. The heart of the shoots is especially delicious. Depending on the species, young shoots can be harvested from late winter and for much of the spring. However, some caution is needed, since there is a report that eating large quantities of the leaves causes hallucinations. Blanching the leaves is said to remove this hallucinatory component, but the report does not make clear what it means by blanching, it could be excluding light from the growing shoots or immersing them in boiling water. As far as is known, eating the cooked leaves is perfectly all right, and you would need to eat several pounds of raw leaves to experience the effect.

Many species also produce tuberous roots, or fibrous roots with occasional spindle-like swellings. These roots are also edible raw or cooked and have a very pleasant nutty flavour that is like a blend of sweetcorn and salsify. Young tubers are the best, though the central portion of older roots can also be used. Don't expect large crops of roots though, this will be just an occasional bonus crop when you are dividing plants.

Hemerocallis also has a number of other uses. Many species make a very good weed-excluding ground cover, succeeding under and around trees and shrubs in low-maintenance gardens. Plant clump- forming species such as H. dumortieri, H. lilioasphodelus and H. middendorfii about 18 inches apart each way. Running species such as H. fulva can be planted up to 1 yard apart. Since the plants die down for the winter, the dead leaves should be left on the ground to ensure effective cover.
Whilst young leaves are sweet and tender, the older leaves become very fibrous. These tough fibrous leaves can be dried and plaited into a cord, then used for making footwear etc. The shoes are not going to be that hard wearing, nor will they be waterproof, but they will make a good sandal for the summer.

There are also a number of medicinal properties attributed to these plants. In particular, the juice of the roots is an effective antidote in cases of arsenic poisoning and the roots also have a folk history of use in the treatment of cancer. 

The species

Let's move on now to look at a few of the most interesting species in the genus.

Hemerocallis dumortieri  is a vigorous clump-forming species that grows about 1ft 8ins (0.5m) tall. Each flowering stem carries up to eight trumpet-shaped flowers that are about three inches long. This is one of the first species to come into flower, in early summer, each flower living less than a day. It is also quite early coming into new growth and makes a good ground cover.

Hemerocallis fulva. This species is one of the most interesting for the gardener, as well as being perhaps the best one as an edible crop. A running species, it grows about 3ft tall and will spread as far as you let it. This species is so vigorous that it has been known to grow through tarmac! It flowers in mid summer. There are a number of named forms, most if not all of which are sterile triploids and will not produce seed. The pollen, however, is fertile and can be used to fertilize other plants. Cultivated for its flowers in China and Japan, they are usually harvested as they start to wither and then dried. But perhaps they are best eaten raw when they are fully open; they have very thick petals and are deliciously crunchy - ideal for salads or a munch in the garden. The roots have edible spindle-shaped swellings.

There are a number of named forms of special interest as food plants. Their nomenclature is somewhat confusing; the first three cultivars are listed below under the names given when they were obtained them from a nursery.
All of these first three have double flowers, so you get a lot more petals for your flower!

Kwanso is a variegated form with white stripes along the length of the leaves

Green Kwanso is very similar to the above, except its leaves are not variegated. Its roots are somewhat larger than average.

Flore Pleno is rather similar to Green Kwanso. The flowers are about 6 inches long. This is the form that is most commonly used in China for its flowers.

Europa is a very vigorous form that is especially good for ground cover. I have been unable to obtain this form so far, if you happen to know of a source then I would love to hear from you.

Hemerocallis lilioasphodelus is a clumping species growing about 3ft tall, with lovely yellow flowers. These look very attractive in a salad but a word of caution is needed.  Most people find the taste delicious but some  women who try it say that it leaves a very unpleasant aftertaste in the mouth, and on a couple of instances this has been likened to sweaty armpits. The plant has a long flowering season during summer, and individual flowers live longer than in most species, sometimes for three days. The plant has a fibrous root system with occasional spindle-like edible swellings.

Hemerocallis middendorffii esculenta is a vigorous clumping plant growing about 2ft tall. It is cultivated in the Orient for its edible flowers and so should be well worth growing. The flowers, which are produced in early summer, are up to 4 inches long with 5 - 6 blooms carried on each flowering stem. This species does not have swollen roots.

Hemerocallis minor grows about 1ft 8ins tall, flowering in late spring/early summer. The flowers are about 2 inches long with, up to 5 being carried on each flowering stem.

If you want a tasty food crop that is easily grown and also very ornamental, then this genus must be worthy of consideration.

Database

The database has more details on these plants: Hemerocallis dumortieri, Hemerocallis fulva, Hemerocallis littorea, Hemerocallis fulva longituba, Hemerocallis lilioasphodelus, Hemerocallis minor.