To carry on hot-beds on a large scale successfully is almost an art in itself, and for fuller details I will refer my readers to works on gardening. Early plants, in a small way, may be raised in flower pots or boxes in a warm kitchen window. It is best, if practicable, to have but one plant in each pot, that they may grow short and stocky. If the seed are not planted earlier than April, for out-of-door cultivation, a cold frame will answer.

For a cold frame select the locality in the fall, choosing a warm location on a southern slope, protected by a fence or building on the north and north-west. Set posts in the ground, nail two boards to these parallel to each other, one about a foot in height, and the other towards the south about four inches narrower; this will give the sashes resting on them the right slope to shed the rain and receive as much heat as possible from the sun. Have these boards at a distance apart equal to the length of the sash, which may be any common window sash for a small bed, while three and a half feet is the length of a common gardener's sash. If common window sash is used cut channels in the cross-bars to let the water run off. Dig the ground thoroughly (it is best to cover it in the fall with litter, to keep the frost out) and rake out all stones or clods; then slide in the sash and let it remain closed for three or four days, that the soil may be warmed by the sun's rays. The two end boards and the bottom board should rise as high as the sash, to prevent the heat escaping, and the bottom board of a small frame should have a strip nailed inside to rest the sash on. Next rake in, thoroughly, guano, or phosphate, or finely pulverized hen manure, and plant in rows four to six inches apart. As the season advances raise the sashes an inch or two, in the middle of the day, and water freely, at evening, with water that is nearly of the temperature of the earth in the frame. As the heat of the season increases whitewash the glass, and keep them more and more open until just before the plants are set in open ground, then allow the glass to remain entirely off, both day and night, unless there should be a cold rain. This will harden them so that they will not be apt to be injured by the cabbage beetle, as well as chilled and put back by the change. Should the plants be getting too large before the season for transplanting, they should be checked by root pruning,—drawing a sharp knife within a couple of inches of the stalk. If it is desirable still further to check their growth, or harden them, transplant into another cold frame, allowing each plant double the distance it before occupied.

The structure and management of a hot-bed is much the same as that of a cold frame, with the exception that the sashes are usually longer and the back and front somewhat higher; being started earlier the requisite temperature has to be kept up by artificial means, fermenting manure being relied upon for the purpose; and the loss of this heat has to be checked more carefully by straw matting, and, in the far North, by shutters also. In constructing it, horse-manure, with plenty of litter, and about a quarter its bulk in leaves, if attainable, all having been well mixed together, is thrown into a pile, and left for a few days until steam escapes, when the mass is again thrown over and left for two or three days more, after which it is thrown into the pit (or it may be placed directly on the surface) which is lined with boards, from eighteen inches to two feet in depth, when it is beaten down with a fork and trodden well together. The sashes are now put on and kept there until heat is developed. The first intense heat must be allowed to pass off, which will be in about three days after the high temperature is reached. Now throw on six or eight inches of fine soil, in which mix well rotted manure, free from all straw, or rake in, thoroughly, superphosphate, or guano, at the rate of two thousand pounds to the acre, and plant the seed as in cold frame. Harden the plants as directed in preceding paragraph.