Is the simplest, and least satisfactory form of advance work in the garden; it belongs in the class of being "better than nothing," but for some plants is quite as successful as a hotbed, unfortunately that particular class is not embraced in a book on vegetable gardening, but belongs particularly to flower gardening and the special sorts dedicated to the warm conservatory and window garden.
However, if one has not, and cannot achieve, the advantage of a hotbed then one must make the most of what is attainable and resort to flats. These may be of any shape or size, but the usual florists' flats—about fifteen inches wide and twenty long and not over five inches deep—are of a practical size for general use; narrower ones which may be set on a window sill are also useful but will not give a large number of plants. Very convenient plant boxes which simulate a miniature hotbed, being about six inches high in the back and about four in front, of the usual flat size and supplied with a hinged lid of glass, are sold by the florists but are easily manufactured at home and are better than the open flats as they enable one to regulate moisture, the principal trouble—owing to the dry air of the living rooms, the shallowness of the soil, in growing plants in flats.
Several holes for drainage should be made in the bottom of the boxes and these covered with pieces of shard or glass and the boxes filled to within a half inch of the top with a good compost consisting of fibrous loam—that shaved from the bottom of sods—leaf mould, clean white sand and a little well-rotted manure, all thoroughly mixed and free from roughage.
The seeds should be broadcasted, if fine, drilled in if coarse, and the soil pressed down snugly over them. In the case of fine seed it is a good idea to cover with fine white sand instead of soil as this is less subject to the minute fungus which causes the deadly "damping off" so destructive to plant life and especially troublesome in growing plants in the house.
As in the planting in the hotbed, the seed plots should be carefully labeled with name and date of sowing. After planting the seeds the flats should be set in a pan of water until the surface looks dark but not wet. They should then be covered with a sheet of white paper and glass and set in a warm, sunny window until germination takes place. Then the glass should be raised sufficiently to admit air and the paper removed and placed between the box and the window or a width of cheese cloth may be interposed between the glass and the box to temper the sunlight until the little plants have acquired their first pair of true leaves when they will be able to endure more heat and air which should be steadily increased until on mild days the window may be opened that they may benefit by full sunshine and air. As soon as the little plants are an inch high, transplant into other flats, setting an inch or more apart each way, and grow on as before or until they again crowd each other, when they may be transferred to small two or three inch pots and the sand box until time to go into the ground.
[1] Or a trench as deep as the completed pit and as narrow as can be handled may be dug to outline a pit of the required dimensions, and filled with grout, well tamped down; when this has had time to harden sufficiently, the earth may be removed from the center and the cement given a finishing coat, and the wall brought to the required height above ground by the aid of a frame of boards.