Bulbs flowering through the winter add to the list of house plants a charming variety. The labor, time, and skill required is much less than for growing many of the larger plants more commonly used for winter decorations (for instructions on growing bulbs out-of-doors, see p. 281; also the entries in Chapter VIII).
Hyacinths, narcissus, tulips, and crocus, and others can be made to flower in the winter without difficulty. Secure the bulbs so as to be able to pot them by the middle or last of October, or if earlier all the better. The soil should be rich sandy loam, if possible; if not, the best that can be got, to which about one-fourth the bulk of sand is added and mixed thoroughly.
If ordinary flower-pots are to be used, place in the bottom a few pieces of broken pots, charcoal, or small stones for drainage, then fill the pot with dirt so that when the bulbs are set on the dirt the top of the bulb is even with the rim of the pot. Fill around it with soil, leaving just the tip of the bulb showing above the earth. If the soil is heavy, a good plan is to sprinkle a small handful of sand under the bulb to carry off the water, as is done in the beds outdoors. If one does not have pots, he may use boxes. Starch boxes are a good size to use, as they are not heavy to handle; and excellent flowers are sometimes secured from bulbs planted in old tomato-cans. If boxes or cans are used, care must be taken to have holes in the bottoms to let the water run out. A large hyacinth bulb will do well in a 5-inch pot. The same size pot will do for three or four narcissuses or eight to twelve crocuses.
After the bulbs are planted in the pots or other receptacles, they should be placed in a cool place, either in a cold pit or cellar, or on the shady side of a building, or, better yet, plunged or buried up to the rim of the pot in a shady border. This is done to force the roots to grow while the top stands still, as only the bulbs with good roots will give good flowers. When the weather gets so cold that a crust is frozen on the soil, the pots should be covered with a little straw, and as the weather gets colder more straw must be used. In six to eight weeks after planting the bulbs, they should have made roots enough to grow the plant, and they may be taken up and placed in a cool room for a week or so, after which, if they have started into growth, they may be taken into a warmer room where they can have plenty of light. They will grow very rapidly now and will want much water, and after the flowers begin to show, the pots may stand in a saucer of water all the time. When just coming into bloom the plants may have full sunlight part of the time to help bring out the color of the flowers.
Hyacinths, tulips, and narcissus all require similar treatment. When well rooted, which will be in six or eight weeks, they are brought out and given a temperature of some 55° to 60° till the flowers appear, when they should be kept in a cooler temperature, say 50°. The single Roman hyacinth is an excellent house plant. The flowers are small, but they are graceful and are well adapted to cutting. It is early.
The Easter lily is managed the same way, except to hasten its flowers it should be kept at not lower than 60° at night. Warmer will be better. Lily bulbs may be covered an inch or more deep in the pots.
Freesias may be potted six or more in a pot of mellow soil, and then started into growth at once. At first they may be given a night temperature of 50°; and 55° to 60° when they have begun to grow.
Small bulbs, as snowdrop and crocus, are planted several or a dozen in a pot and buried, or treated like hyacinths; but they are very sensitive to heat, and require to be given the light only when they have started to grow, without any forcing. Forty to 45° will be as warm as they ever need be kept.