Soils for growing early vegetable plants should absorb water readily and dry quickly on the surface. A sandy loam furnishes ideal conditions. Heavier soils can be improved by the addition of sand and rotten manure. Suitable soil for this work can often be found in garden or field, or it may be prepared by composting. The most convenient method of preparing soil for this purpose is to select a suitable area and apply manure freely. Spread the manure to the depth of 4 or 5 inches, plow the land and harrow once or twice. This work should be attended to in the spring as soon as the ground is dry enough for plowing. After the manure is partially decayed, plow and harrow again, and repeat these operations occasionally during the summer. The soil should be in excellent condition for storage in the fall.
Manure and sod, stacked in alternate layers of 4 to 6 inches deep, also make a soil of superior character for starting early plants. When soil is prepared in this manner, about a year is required for the thorough decay of the materials composted. Shoveling the pile over a few times during the latter part of the period of composting helps to secure a fine and well-mixed soil. Whatever soil is selected or prepared great care should be exercised to avoid germs of troublesome diseases. For example, soil for raising cabbage plants should never be taken from a field where any plants of the cabbage family have been recently grown. When dry enough to handle without injuring the texture, it should be stored under cover where it will not be in a frozen condition when wanted for use.
Flats are often used in greenhouses, and they are practically indispensable when starting plants in hotbeds and cold frames. Notwithstanding this, many gardeners do not use them extensively, for they have not learned their advantages, which may be enumerated as follows: (1) They make it possible to do all the work of seed sowing and transplanting in warm, comfortable rooms provided with tables or benches of convenient height. Because of these comforts and conveniences, more work can be accomplished in a day, especially if the weather is cold or disagreeable, and it will be done better than when the worker must stoop over frames. (2) Sowing or transplanting may be continued whatever the character of the weather. When transplanting in severe weather, the box of plants should be protected by a cloth or a box when carried to the work room. So should the plat of transplanted seedlings when taken to the cold frame. (3) Many growers claim that they can grow better plants in flats, because moisture conditions are more perfectly controlled. (4) Each flat contains a uniform number of plants, and this is a great advantage when making sales. (5) In shipping, the flats of plants may be crated, if this is desired, and they will reach their destination in perfect condition. (6) When planting in the field the flats may be hauled and distributed over the field at convenient intervals. (7) The plants may be pulled with a large amount of soil, as shown in Figure 38. Some gardeners go to the trouble of cutting out each plant with a block of soil or of compost.
Flats may be made from soap boxes or other boxes of convenient size. This is doubtless the most economical plan, but there are objections to it. The lumber in a miscellaneous lot of boxes is variable in quality and durability, and the flats are not uniform in size. Because of varying dimensions they cannot be placed in the frames without loss of space. When this annual loss is taken into account, it makes a strong argument for a uniform size of flats. When new lumber is used, the flats should be made to fit in the frames or on the greenhouse bench without loss of space. Chestnut is a durable wood for this purpose. The sides and bottoms should be made of «-inch and the ends of ¾-inch pieces. When nailing on the bottom pieces, about ¬-inch cracks should he left between them, to provide good drainage. Two inches is ample depth for most purposes. A deeper flat requires more soil and makes handling heavier. If the flats are about 2« × 16 × 22« inches, outside dimensions, three of them will fit in a 6-foot frame without an appreciable loss of space. Flats of smaller size are convenient for the retail plant business.
Various kinds of mats are used to protect plants in hotbeds and cold frames. In some sections lath crates about 3 inches thick, stuffed with fine hay or sea weeds, are used for this purpose. They furnish excellent protection, but are heavy and inconvenient to handle. Burlap mats stuffed with cotton waste are on the market, but they are difficult to keep on the frames in windy weather; they furnish poor protection when wet and are lacking in durability. Canvas mats are satisfactory, but are too expensive for general use. When all points are considered, rye-straw mats are most serviceable; they are inexpensive, are not easily displaced by even hard winds and furnish thorough protection. Machine-sewed mats of this type, as illustrated by Figure 40, are on the market, or they can be made by hand. The mats made by machine are uniform in thickness and are much neater than can possibly be made at home, unless an unusual amount of time is spent on each mat. When not in use, mats should be stored under cover where rats and mice will not damage them. With good care they will last several years. A mat is generally large enough to cover two sash, 6 × 6« feet being the popular size.