This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(Greek name for a lily). Amaryllidaceae. Large and showy flowering bulbs, mostly tender, closely allied to Amaryllis and distinguished by the longer perianth-tube; flowers usually white or in shades of red; largely summer bloomers, but differing widely in this respect.
Stems arising from a tunicated bulb with a more or less elongated neck: leaves mostly persistent, usually broad, sometimes several feet long: flowers few or many in a 2-bracted umbel, often very fragrant and with 3 types of coloring, pure white, banded red or purplish down the center, or flushed with the same colors; perianth salver-form or funnel-shaped, the tube straight or curved, long-cylindrical; segments linear, lanceolate or oblong, nearly or quite equal; stamens 6, attached on the throat of the corolla, with long filiform filaments and very narrow versatile anthers; ovary 3-celled, the ovules few in each cell, the style long and filiform, somewhat bent downward, the stigma not lobed: fruit a roundish or irregular caps., at length dehiscing; seeds large, green, thick. - Probably 100 species in warm and tropical regions around the world, in moist or wet places. The crinums are amaryllis-like plants of great beauty. They are widely grown, often under the name of "lilies," some of them as warmhouse plants, some as coolhouse subjects, and a few as hardy border plants. The bulbs are often very large, sometimes as much as 2 or 3 feet long, neck and all, the leek-like neck gradually tapering from the bulb proper.
In some species the bulb is short and onion-like. Fig. 1108 shows forms of crinum bulbs. In some species the flowers are 1 foot long and half as broad; and sometimes the leaves reach the length of 6 feet and a width of 5 or 6 inches. The flower-stalk is solid, leafless, usually arising from the side of the bulb-neck. The genus might be roughly divided into the evergreen kinds, mostly with leek-like bulbs and symmetrical star-like straight-tubed usually erect flowers; and the deciduous-leaved kinds, mostly with roundish bulbs and nodding bell-shaped more or less irregular flowers.
Fig. 1108. Crinum bulbs as named in the trade. Left to right, C. Moorei, C. giganteum, C. Kirkii, C. Powellii.
The crinums require so much room that they are not often seen in commercial collections in this country. They are particularly adapted to mild and warm climates, and therefore full notes on such handling of them are given here. They are not much grown in American greenhouses. The species cross freely, and many fine hybrids are known, some of them under Latin species-names.
The species of Crinum require widely different culture, and their geographical distribution furnishes an important clue as to the degree of warmth required. There are two species hardy in the northern states, C. longifolium and C. Moorei, the latter being less reliable than the former but with finer flowers. These two species differ from others in blooming all summer instead of during a short period, and in the more lasting qualities of their flowers. An interesting hybrid between the two, C. Powellii, is hardier than C. Moorei, and the flower, though better than C. longifolium, is not quite so showy as that of C. Moorei. The hybrid has three well-marked colors, white, rosy and purplish. A single bulb of the white variety has given fifty flowering bulbs in four years. It is excellent for placing in conspicuous positions on terraces or lawns, or in corners where flowers are wanted to combine with architecture or statuary for summer effect. The Agapanthus is frequently grown also for such purposes. Of course large specimens are needed for this use, but they are easily secured and they last from year to year.
The bulbs of crinums are mostly grown in Holland and in Florida. The only native species, C. americanum, the "swamp lily of Florida," makes a brilliant and striking spectacle when seen in places far from cultivation, as in the Everglades.
The most reliable of the hardy crinums in the North is probably C. Powellii. If the bulbs are planted 2 1/2 to 3 feet deep (to the bottom of the bulb) in well-drained soil, the plant stands without protection in the neighborhood of New York City. Let them stand 2 to 3 feet apart. This crinum makes a very ornamental summer plant, even the strong foliage producing a tropical effect. It produces offsets very freely, but they are deep in the ground. It seems not to produce seed in the North. C. longifolium is also hardy, but is better with a covering in winter; and it is inferior to C. Powellii in leaf and flower. C. Moorei is equally hardy except that the bulbs grow near the surface and are therefore so much exposed as often to be ruined by frost. It is a very desirable summer species. It often seeds in the latitude of New York City; and these fleshy seeds germinate readily if placed on the surface of moist soil. It produces offsets freely, which are used in propagation. It has very strong fleshy roots; and when grown in pots or tubs (which is a desirable practice) it should be given plenty of room. This species has a long columnar neck with a spreading cap or crown of leaves, and large white or pink flowers.
C. variabile (C. capense) is hardy south of the Ohio. There are a number of half-hardy species; and most of the greenhouse kinds make very desirable lawn or porch plants when well established in large pots or tubs.
There are more than fifty species of greenhouse crinums, all of them worth growing because of their handsome flowers; some of them have very ornamental foliage. Most of the species are seldom seen in this country, possibly because they occupy too much space and give a comparatively small number of flowers to recompense the grower for their upkeep. It is not necessary to keep the evergreen species growing all the time after the flowers have been produced. The plants may be put out-of-doors under a lath-house for four or five months. The soil should be of a lasting nature with good drainage so that frequent repotting will not be necessary. When the plants are in a growing state, frequent applications of manure water will be found to be beneficial. In the warmer parts of the country, many of the tropical species should be plunged or planted out in the open border, where they often give a satisfactory quantity of flowers. In winter, the plants may be carried over under the bench of a temperate house.
They should be given water occasionally during April and the first half of May to encourage new root-growth." When planted out in rich soil, nearly all of them will produce their gorgeous flowers out-of-doors; and during winter they are best treated as dormant bulbs with a little more heat than given such plants as cannas and richardias, planting them out as soon as the weather is favorable. A few of the tropical crinums are grown for their foliage principally, and are often seen in public conservatories and palm-houses where they suffer but little from dense shade. The flowers of most species are exceedingly handsome but only for a comparatively short time; during the remainder of the year when out of bloom there are hosts of things that are much more ornamental. Tropical crinums should be grown in this country nearly altogether for outdoor work; we then get the best out of them because our hot summers are favorable to their growth and for the production of bloom. Those species not amenable to this treatment do not give results at all in keeping with the space and time devoted to them. (G. W. Oliver.)