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LILIUM (Latin, from the Greek name, said to be derived from the Celtic word li, meaning whiteness, referring to L.candidum). Liliaceae. Lily. Noble plants for outdoor bloom, and a few of them grown under glass. They comprise one of the distinctive flower forms, and the name lily is applied to many other plants.
Herbaceous perennials with scaly bulbs: sts. unbranched, smooth or pubescent, usually bright green, sometimes tinged purple or brown and generally clothed with leaves their entire length: leaves (except in only 2 species, L. cordifolium and L. giganteum) always linear or lanceolate, either scattered or verticillate, usually bright green and quite sessile, but in a few species with short petioles: flowers terminal, solitary, racemose or umbellate, perfect, with 6 perianth-segms., 3 like sepals or calyx-leaves and 3 like petals or corolla-leaves, the parts erect or variously spreading or reflexed, usually with a honey-bearing gland at the base of each; each; each flower has 6 prominent stamens and 1 long pistil; each stamen consists of a filament or stalk and an anther balanced on its end and attached by its back, while the ovary bears a style and a 3-lobed stigma: the fruits or seed-vessel is an oblong caps, borne above the base of the perianth-segms.; it is (Cribbed, divided into 3 cells, each cell closely packed with flattened, brown, soft-coated seeds. The genus is divided into 7 groups or subgenera, distinguished from each other chiefly by the shape and arrangement of the flowers These groups are:
I. Eulirion (true lilies, trumpet-or funnel-flowered lilies).
II. Archelirion (open-flowered lilies).
III. Martagon (Turk's-cap or turban-shaped lilies).
IV. Pseudo-Martagon (bell-flowered lilies).
V. Isolirion (erect- or upright-flowered lilies).
VI. Cardiocrinum (heart-shaped-leaved lilies).
VII. Notholirion (fritillaria-like lilies).
From 300-400 species have been described, but there are probably considerably less than 100 entitled to rank as such. They are all natives of the northern hemisphere, extending around the world. Their northern limit is southern Canada and Siberia; their southern, Florida and the Neilgherry Mts. of India. Many of them are in California and China-Japan.
The genus Lilium is very closely allied to Fritillaria; the latter genus differs in the corolla being more uniformly campanulate, with nectar-bearing cavities at the base of the inner segms. or of all of them, and the anthers attached by the base. Lilium roseum is by some referred to Fritillaria, but it is probably better kept in Lilium. L. oxypetalnm is a similar case.
For further botanical information, the reader is referred to "The Botanical Gazette," 27:235 (1899), where a botanical review of the genus will be found. The most notable monograph on lilies is entitled "A Monograph of the Genus Lilium," by H. J. Elwes, published in 1880 and containing superb colored plates. It is referred to below by the abbreviation El. It covers the ground fully up to the date of publication. Unfortunately there is no book yet published which combines the botanical and horticultural points of view, but much valuable cultural information may be obtained by reading the following four books: Wallace's "Notes on Lilies," 2nd edition; "Lilies for English Gardens," by Miss Jekyll; "The Book of the Lily," by Wm. Goldring, and "Lilies," by Adams and one by A. Grove. Many portraits have been made of species of Lilium, some of the most important and accessible of which are cited in the following account. The author cannot vouch for the authenticity of these portraits, however.
''The general cultivation of lilies''.
The various lilies are unequaled by any other plant in their unique combination of beauty, gracefulness and stately magnificence; yet they are entirely unknown in many gardens, while in others only a few of the commoner species, like L. candidum, L. speciosum or L. tigrinum are seen. Their culture has been entirely too much neglected in this country, but we are confident that, as their merits become better known, they will be much more largely grown. Many persons seem to have an impression that lilies are difficult to grow and perhaps this is one reason why they are not cultivated more generally. It is true that a few species, as noted in their descriptions, are of rather difficult culture, sometimes succeeding well but more often failing simply because one does not fully understand their needs. It must be remembered that, in their native habitats, the different lilies are found under widely varying conditions of soil, climate and environment, and some kinds are so delicate and capricious that they will not succeed well under cultivation unless the peculiar conditions under which they are found in a wild state can be closely imitated. But, on the contrary, most lilies are robust, long-lived and of easy culture under a variety of soil and climatic conditions. The beginner in lily-culture should always select these easily grown kinds, choosing them according to his own individual taste. There are enough of these to satisfy any ordinary cultivator, unless he becomes an enthusiast or specialist, desirous of securing as large a collection as possible of different species and varieties. In that case, and if space, time and means will permit, he may attempt the culture of the more capricious sorts. The following is a selection of twelve of the best easily grown lilies for general cultivation: L. candidum, L. regale, L. auratum var. platyphyllum, L. speciosum var. magnificum, L. tigrinum var. splendens, L. monadelphum, L. superbum, L. testaceum, L. Martagon var. glabrum, L. tenuifolium, L. croceum, L. dauricum var. incomparabile.
By using care and judgment, suitable lilies may be chosen for almost any location or purpose. Nearly all species are desirable for planting in combination with other hardy perennial plants or scattered among dwarf- growing shrubs in such a manner that the flowers will rise above their foliage, thus imitating nature, for in a wild state the lower part of the stem of many species is thickly surrounded with grass or dwarf undergrowth, while the upper part and flowers rise free. Many lilies also produce a charming effect when planted in front of large shrubs, such as magnolias and rhododendrons, the flowers showing up well against the background of green. For large beds or massing, only such kinds as produce a showy display of flowers should be chosen. L. candidum, L. dauricum, L. elegans, L. speciosum, L. tigrinum and their varieties are especially desirable for this purpose. Sometimes different species or varieties are planted together in the same bed, but, unless space is limited, it is usually better to keep them separate. Any of the strong-growing permanent lilies, L. superbum, L. tigrinum, and many others, are excellent for naturalizing in wild or uncultivated ground. Some of the smaller-growing kinds, like L. concolor, L. elegans, L. tenuifolium, are desirable for planting in rock-gardens with other plants. In the northern states the capricious sorts, like L. japonicum and L. Leichtlinii, often succeed better when grown in coldframes or pots than in the open ground, and if their culture is attempted this method is recommended.
The flowers of all lilies, with the exception of a few ill-smelling species, are excellent for cutting. Only the upper part of the stem should be cut off, however, leaving the foliage on the lower part, so the bulb may complete its growth. If the stem is cut off right down to the ground when in active growth, the bulb will be injured or perhaps destroyed.
''Soils and location''.
Most lilies will succeed in any light, sandy or loamy soil. Decayed peat or leaf-mold may be added with advantage, as the American species are especially partial to a peaty soil. Some species, like L. candidum, L. croceum, L. elegans, L. Hansonii, L. monadelphum, L. tigrinum and most of the European Turk's-cap lilies will also do well in a heavier soil, even clay if it is well drained. Good drainage is an essential point, for no lilies, with the possible exception of L. canadense and L. superbum, will live in a wet or swampy soil, where stagnant water stands around the bulbs. Whenever possible, a slightly sloping location with a porous gravelly subsoil should be chosen. Several species, like L. candidum, L. chalcedonicum, L. carniolicum, L. Hansonii, L. monadelphum, L. Martagon, L. pomponium, L. testaceum and a few others will thrive in a calcareous or limestone soil, but lime is poison to most lilies and with these exceptions they should never be planted in soils containing it. Of whatever nature the soil, it should be fairly rich and if not naturally so a liberal quantity of thorougly decayed cow- or sheep-manure should be mixed in before planting the bulbs. In after years, additional nourishment may be provided by top-dressings of decayed manure. Fresh manure of any kind should never be used, as it attracts worms and causes the bulbs to decay.
Although, as noted above, good drainage is necessary, yet lilies like plenty of moisture when in active growth. Frequent shallow cultivation or mulching will help to conserve the moisture already in the soil, but in periods of drought artificial watering may be necessary.
Some lilies, as L. candidum, L. croceum, L. elegans, L. Martagon, L. monadelphum and L. tigrinum, will often succeed very well in full sunshine and exposure. Others, however, like L. auratum, L. Hansonii, L. Henryi, L. japonicum, L. Parryi, L washingtonianum, often fail or the flowers bleach or fade quickly in such situations. As a rule, however, it may be said that all lilies will thrive better in partial shade, and the flowers will last longer. The ideal location is under trees or large shrubs, but far enough away so that their roots will not rob the lilies of moisture and nourishment. In such places, they will receive a free circulation of light and air, but the full force of the hot midday sun cannot reach them.
''Protection from cold and wind''.
In cold climates, the bulbs of all lilies should be protected from freezing during winter by a heavy covering of leaves, hay or straw. Some species, as L. bulbiferum, L. candidum, L. slogans, L. tigrinum, are apparently not greatly injured if the bulbs freeze, but frost is fatal to many, especially the Californian and Indian species, and even the hardiest kinds will do better if the bulbs are protected from it. Frost sometimes also injures the tender young growth of L. auralum, L. chalcedonicum, L. Hansonii, L. longiflorum, L. speciosum, L. testaceum and others which appear above ground very early in spring. This can be prevented by covering the plants with old sheets, or something similar, on cold nights when frost is expected.
To prevent the stems of lilies from being broken by high winds, each plant or clump should be supported with a stick or stake, preferably of bamboo, tying them together with soft yarn or twine. It is better, however, wherever possible, to plant lilies in such a way that they will not require staking, as this deprives them of their natural gracefulness of swaying with the breeze.
''The planting''.
The best time to plant lily bulbs is soon after the flowers fade or seeds ripen. They cannot always be obtained at that time, however, imported ones often not being received until late in autumn or winter. In the northern states, the places intended for these late- received bulbs should be prepared previously and covered with 5 or 6 inches of leaves or litter, to prevent the ground from freezing. This should be removed and the bulbs planted as soon as received, afterward replacing it as a winter mulch. Or, if preferred, the bulbs may be packed in boxes of sand, leaf-mold or sphagnum moss and stored in a cool dark frost-proof cellar, closet, or shed until spring, when they should be planted. The material they are packed in must be kept constantly moist, neither too wet nor too dry. In this connection it might be well to add a few words of advice in regard to the purchase of lily bulbs. Whenever possible, freshly dug home-grown bulbs should be secured or at least those which have been shipped only short distances, which have not been deprived of their roots, and whose scales have not become dried or shriveled. Such bulbs, although they may cost more than imported ones, which have often been kept out of the ground for several months, are well worth the difference.
No definite rules can be given in regard to the proper depth and distance apart to plant the bulbs, but usually they should be set so that their top or apex will be three times as deep as their greatest diameter. The smaller- growing species, as L. concolor. L. elegans, and L. tenuifolium, may be planted about 6 inches apart, while from 12 to 18 inches is not too much space for the largest species, like L. auralum, L. tigrinum, and so on. When planting the bulbs, it is a good plan to surround each one with sand or fine gravel, which helps to drain away surplus moisture and also tends to repel worms. Some growers also place a handful of fresh sphagnum moss under each bulb, thinking it induces a better root-growth.
It is the nature of many lilies to throw out annual fibrous roots from the underground stem above the bulb (called stem-roots), in addition to the large permanent ones at its base (called basal or bulb-roots). The following species and their varieties belong to this class: L. auratum, L. Batemanniae, L. Brownii, L. bulbiferum, L. concolor, L. croceum, L. dauricum, L. elegans, L. Hansonii, L. Henryi, L. japonicum, L. Leichtlinii, L. longiflorum, L. Maximowiczii, L. medeoloides, L. odorum, L. regale, L. rubellum, L. Sargentiae, L. speciosum, L. sulphureum, L. sutchuenense, L. tigrinum and L. Wallacei.
The following species and their varieties produce but few, if any, stem-roots: L. Bolanderi, L. callosum, L. canadense, L. candidum, L. carniolicum, L. carolinianum, L. chalcedonicum, L. columbianum, L. giganteum, L. Grayi, L. Humboldtii, L. Kelloggii, L. maritimum, L. Marlagon, L. monadelphum, L. pardalinum, L. Parryi, L. parviflarum, L. parvum, L. philadelphicum, L. pomponium, L. pyrenaicum, L. Roezlii, L. superbum, L. tenuifolium, L. ttstaceum and L. washingtonianum.
The bulbs of these non-stem-rooting species, when not received or planted until late autumn or spring, often remain dormant until the second summer, because the basal roots, on which the flower-stem must depend entirely for its support, have been cut off or dried up by exposure to the air, and consequently the bulbs are so weakened that it takes them a year or more to recover and form new roots. Sometimes, however, a small weak stem develops the first summer, which soon perishes without flowering. On the contrary, the stem- rooting species usually bloom well the first summer after planting, because, even if the bulbs do not produce roots they are formed at the base of the stem, which is nourished and supported by them.
''Propagation''.
Lilies are propagated by division of the offsets, by bulbils, by scales or by seeds. The best and easiest method with most species is by division of the offsets, which form at the base of the parent bulb, on the underground stem above the bulb, or on the end of a rhizome. The best time to do this dividing and replanting is from two to four weeks after the flowers fade or immediately after seeds ripen, as that is the only time the bulbs are really dormant and many species greatly dislike to be disturbed when the roots are in active growth. The clumps should be carefully dug up and the large flowering bulbs planted immediately where they are to remain permanently, while the smaller ones may be planted in beds by themselves, removing them to their permanent location when they become large enough to bloom, which will usually be in two or three years.
Sometimes, when separating and replanting the bulbs, fresh healthy scales become detached. If these are planted in rows 2 inches apart and 1 or 2 inches deep, in light sandy soil, either in boxes, coldframes or the open ground, one or more tiny bulbs will usually form at the base of each scale, where it was broken off. These will become large enough to bloom in two or three years.
L. bulbiferum, L. Sargentiae, L. suphureum and L. tigrinum and its varieties usually produce small dark green or purple bulbils or bulblets in the upper leaf- axils. If these are removed before they drop to the ground and planted, like the detached scales, they will bloom in two or three years.
Raising lilies from seeds is very interesting, but it requires time, care and patience. Under favorable conditions, most lilies will produce seeds, but a few species often remain sterile, unless the flowers are hand-fertilized. Among these may be mentioned L. Brownii, L. candidum, L. Hansonii, L. longiflorum, L. speciosum, L. sulphureum, L. testaceum, L. tigrinum, L. Wallichianum and some varieties of L. elegans. Freshly-gathered seeds, sown soon after they ripen, will germinate more quickly than those which have been kept until they become hard and dry, but in all cases the period of time required for germination varies greatly with the species. For example, fresh seeds of L. tenuifplium will often germinate in a month, or even less, while those of L. auratum and many others will seldom germinate until the following spring and often not until a year later. Similarly, the time required for the seedlings to become large enough to bloom varies greatly. L. philadelphicum, L. tenuifolium and a few others will often bloom the second summer after the seeds germinate, while L. giganteum seldom blooms before five or six years have passed. Most species, however, require three or four years. The seeds should be sown thinly in boxes of light sandy soil, in rows about 2 inches apart and covered about 1/2 inch deep with finely sifted sphagnum moss. The boxes should be kept in the house or greenhouse until the seedlings appear, when they may be set outdoors, in a shady place, during the summer. When the young plants are 2 or 3 inches high, they should be transplanted into coldframes or prepared beds in the open ground, later removing them to their permanent location.
''Insects and diseases''.
Lilies are seldom troubled by insect foes of any kind. Worms will sometimes eat the bulbs, but if they are surrounded with sand, as previously suggested, and fresh manure is never used, they will not be likely to be attacked. Mice will also eat the bulbs and the only way to get rid of them is by poisoning or trapping. Aphis or green-flies occasionally attack the plants, especially when under glass, but they may be readily destroyed by spraying the plants with kerosene emulsion.
There are several fungous diseases that are very destructive to lilies. Probably the worst and most common one is a species of Botrytis. It attacks all kinds of lilies, without any exception, either wild or cultivated, and may appear at any stage of their growth. It is first noticed as buff or rust-colored spots or blotches on the leaves or buds, which soon become covered with a grayish mold. When the disease first appears, all affected parts should be cut off and burned, while the attacked plants, as well as healthy ones growing near them, should be sprayed with some good fungicide, like bordeaux mixture. Then, if the disease persists in spreading, the only thing to do is to dig up the plants, bulbs, roots and all, and burn them.
Another fungous disease, known as Rhizopus necans, is very destructive to imported Japanese bulbs, especially those of L. auratum. It attacks the base of the scales, causing them to decay, and the bulbs, if left exposed to the air for a few days, become soft and rotten and covered with a long white silky fungous growth. As soon as the bulbs are received, they should be carefully examined and those that show the least signs of the disease burned at once, as they seldom recover. Those which appear perfectly sound are often covered with the spores of the fungus and to destroy them the bulbs should be soaked for several hours in a solution of one part carbolic acid to forty parts water. Another method, practised by some growers to prevent the disease from being introduced into their gardens, is to plant the apparently sound bulbs singly in pots or tin cans, and later, those which are healthy and well-rooted should be transplanted to the open ground, while diseased ones should be burned and the soil in the pots sterilized.
The American florists' lily trade. (David Lumsden.)
The lily has become one of the popular plants of the American trade. Its popularity is due not alone to the fact that Lilium longiflorum is the acknowledged Easter lily of commerce, but it is a plant particularly well adapted for church, wedding and other decorations at any season of the year. Lilies are also exceptionally useful as cut-flowers for design work and for Memorial Day trade.
Many million bulbs of L. longiflorum and its varieties are imported from Japan, Formosa and Bermuda each year. It is an exceedingly important commercial crop, and several of the larger eastern and western growers force as many as 200,000 bulbs in a single season.
Lilium longiflorum var. eximium, which is grown under the trade name of L. Harrisii, was for years the principal variety grown for early blooms and for Easter sale. Unfortunately, the variety is attacked by a bacterial disease, and healthy stock is almost impossible to obtain. The lily disease is prevalent in all sections and countries from which the bulbs are imported, and growers find, under forcing conditions, that from 3 per cent to 33 1/3 per cent of the bulbs are affected. L. longiflorum var. eximium is especially susceptible to the disease, but all varieties are now attacked to a greater or less degree. Within the last few years, however, more careful propagation and better cultural conditions have eliminated the disease to a considerable extent, and as a result, there has been an improvement in the crop.
During the earlier period of forcing Easter lilies, they were placed on the market only in the late winter or early spring months. Within recent years, unproved methods of cold storage have made possible the production of blooms of the so-called Easter lilies at any season of the year. However, the larger number of blooms are placed on the market in Easter week, for in the minds of the flower-loving public no other flower is so suggestive of the Easter spirit.
The species of lilies forced under glass may be divided into three groups:
Group I. Lilium longiflorum, Easter lily.
(a) Lilium longiflorum.
(b) Lilium longiflorum, Formosa type.
(c) Lilium longiflorum var. eximium (L. Harrisii).
(d) Lilium longiflorum var. giganteum.
(e) Lilium longiflorum var. multiflorum. ,
Lilium longiflorum var. giganteum is now the most popular for Easter trade; it is also the lily used almost exclusively for cold storage. L. longiflorum, Formosa type, L. longiflorum var. multiflorum, and L. longiflorum var. eximium, are used more especially for earlier flowering.
Group II. Lilium speciosum (L. lancifolium).
(a) Lilium speciosum var. album.
(b) Lilium speciosum var. rubrum.
(c) Lilium speciosum var. roseum.
(d) Lilium speciosum var. Melpomene.
Lilium speciosum ranks next to L. longiflorum as the most valuable for forcing. The varieties album, roseum, and rubrum are the most in demand. They are now forced in winter and spring by using bulbs that have been retarded in the cold storage. The natural blooming period of this species is July and August, and the flowers are then useful for floral designs and cut-flowers
Group III. Lilium candidum (Madonna lily).
There are two forms of L. candidum; one with thin, star-like petals, not much recurved; the other having the broad, stoutly ribbed petals strongly recurved. This latter type is the one most commonly used for forcing. Bulbs of L. candidum are now imported from northern France. Recently, the lily disease has been so prevalent in the Marseilles district that the stock from that section has been less used for forcing purposes.
Forcing of lilies under glass.
When the bulbs are received, they should be potted into suitable-sized well-drained flower-pots, using a compost of three parts of good fibrous loam to one part of well-decayed horse- or cow-manure. There is a difference of opinion as to potting methods. Some growers prefer to place the bulbs first in 4-inch flowerpots, and when a strong root-system has developed, they are shifted into 6- or 7-inch flowering pots. Other growers place the bulbs directly in 6-inch pots, filling them about one-half full of compost, and at a later date when active growth has begun, a rich top-dressing of equal parts loam and cow-manure is added.
When the lilies are first potted, they are placed in a coldframe, watered thoroughly and covered with sphagnum moss, straw, or cinders. Wooden shutters are placed over the frames to keep the bulbs dark and to protect them from rain and heavy freezing. Under such conditions the bulbs will root readily. Before hard frosts, they are removed to a greenhouse and given a temperature of 45° to 50° F. at night for a week or ten days. When top-growth commences, a steady night temperature of 60° F. is maintained, raising the temperature to 70° during the day. Lilies should be given abundant ventilation and the plants should be freely syringed on bright mornings, but the foliage should be dry during the night.
It will require approximately thirteen weeks from the time that the plants are brought into the house to get them into flower, provided a temperature of 60° F. is maintained. It should be remembered, however, that weather conditions are dominant factors in lily- forcing; therefore, allowance must be made for a longer period for forcing if the weather is exceptionally dark or cloudy. Sometimes a slightly increased temperature shortens the period of forcing, and such an increase is not detrimental to the value of the flowers If the buds are forced into flower at too high temperature, however, the keeping qualities of the flowers may be considerably injured. In order to have lilies in their prime for Easter, the buds should show about six weeks previous to that date. They may then be gradually developed, and if they advance too rapidly, they may be placed in a cooler temperature. No group of lilies will develop evenly, and it often requires excellent judgment so to shift the plants into different temperatures that the blooms will open at the proper date. If lilies are too advanced, retarding should not begin until the buds have lost their green color, for when once retarded, it is difficult to start them into growth again. A temperature of 45° to 50° F. at night, with a light shading on the glass, is recommended for developing the flower-buds.
For best success in forcing lilies, the water used for both watering and syringing should be warmed to about 70° F. Soil moisture extremes, caused by over- watering or by neglect, should be avoided.
When the lilies begin to show the buds, a weekly application of liquid manure may be given, using one bushel of cow-manure to fifty gallons of water. If the growth is very slow, three pounds of sodium nitrate may be added to the liquid manure, or it may be used separately in liquid form, using one ounce to one gallon of water.
If the plants are tall, they should be tied erect to neat stakes. Under forced conditions, the lily seems particularly susceptible to attacks of green aphis: therefore, fumigations and spraying with nicotine should be practised regularly throughout the period of growth. If young plants are kept free from aphis, they will be less likely to gain a foothold on the buds. They are particularly injurious to developing buds, for their attacks result in a malformation of the tissue.
Cold-storage lilies.
These are used for planting only from March 1 to September 1, the regular stock being depended on for the remainder of the year. The culture of cold-storage lilies differs from that pursued in the growing of lilies for Easter, as they may be placed in the forcing-house with a temperature of 60° F. immediately after potting. During the warm months, they will bloom in ten weeks from the time started. Those started earlier will require from ten to thirteen weeks.
Lilium speciosum and its varieties are easily grown. The method of culture does not vary much from that of L. longiflorum. They are grown either singly in 6- inch pots or planted in boxes. These boxes are 6 inches deep, and the bulbs are placed about 6 inches apart. The box method of culture is recommended because the roots of the lilies are not so liable to dry out as when pots are used.
Lilium candidum differs from L. longiflorum and L. speciosum in its temperature requirements. Too high temperature is disastrous to it, and a temperature of 50° or 55° F. suits it best. This species is seldom forced except for Easter and Memorial Day trade.
Notes on lily culture.
Allow thirteen weeks from the time the lilies are brought into the greenhouses, to get them into flower. A temperature of 60° F. at night, and 70° F. during the day, will be required.
It will take six weeks from the tune the buds show, to the flowering period.
The best cold-storage temperature for lily bulbs is 34° F.
One of the most satisfactory lilies for Christmas is Lilium longiflorum var. giganteum. The bulbs should be potted September 15. L. longiflorum var. giganteum to be in flower for Easter should be potted in November.
By weekly plantings and proper culture, it is possible to have lilies in bloom throughout the year.
Early shipments of lilies arrive in tune to follow the last of the cold-storage bulbs.
{{Taxobox
{{Taxobox
| color = lightgreen
| color = lightgreen
The plants are summer flowering. Most species are [[deciduous]], but ''Lilium candidum'' bears a basal rosette of leaves for much of the year. Flowers are formed at the top of a single erect stem, with leaves being borne at intervals up the stem.
The plants are summer flowering. Most species are [[deciduous]], but ''Lilium candidum'' bears a basal rosette of leaves for much of the year. Flowers are formed at the top of a single erect stem, with leaves being borne at intervals up the stem.
}}
==Species==
==Species==
