For the convenience of the beginner, I propose to deal with vegetables in groups according to their manner of cultivation First let us consider the ordinary roots grown on every allotment—carrots, parsnips, beetroots, turnips.
All these are crops that are sown where they are to remain. They do not succeed when transplanted, the reason being that transplanting is a shock to the system, and a shock to a plant usually makes it grow old before its time. That is, it makes it cease to grow stems and leaves, and set about the work of reproduction.
In the case of these root crops we do not want them to reach this second stage of plant life. We want them, if possible, to build up an exceptionally rich store of food, packed away in the swollen tap root, so that we can make use of the food on our tables. Any kind of shock during the growing season, such as lack of water for a few days, or disturbance of the soil while hoeing, or an attempt to transplant, or the shock to the root system of meeting with very large stones or with lumps of hot, fresh manure, is likely to make these plants send up flower stems, and when this happens the roots grow coarse and fibrous and unfit for the table.
The first necessity, therefore, is to have a bed dug for these crops, with the soil well broken to a considerable depth, and more or less free from large stones. If the natural soil is particularly stony, it pays to make large deep holes with a crowbar, worked round and round in the soil, and then to fill into these holes some prepared sifted soil, in which the roots will grow happily.
The seeds are usually sown in lines, thinly, and when the seedlings appear they are thinned out. To be sure of making the line, parallel and straight, stretch a line of string across the plot from side to side, attaching it at each end to a sharpened stick, which can be pushed into the soil to hold the line taut. (Remember that the lines should run north and south if possible.) Then, with the edge of the hoe or rake, draw a narrow drill about an inch deep along the line, and scatter the seeds thinly from end to end. If you prefer, or the seed is expensive or scarce, sow just a pinch here and there at intervals of 9 in. or more, according to the distance apart that you intend to leave the mature plants. If you prepare special stations, as suggested above, these too will be spaced according to the amount of space needed by the mature plants.
It is sometimes advisable to thin out in easy stages. For instance, when carrots are sown along a drill, they need not be thinned at first to 8 or 9 in. apart, but may be left about 2 in. apart when the first thinning is done, i.e., when the seedlings are first large enough to handle. Then as the roots grow, alternate ones can be pulled while still small, to flavour soups or to use in the salad bowl, while the others are left to grow on for a bit. At the second thinning alternate roots are once more removed, so that finally as much room as the plants seem to need is left.
Cabbages, cauliflowers, broccoli, Brussels sprouts, savoys, come next in the list of common garden crops raised from seed. It is possible to grow many of these in much the same way as one grows carrots, i.e., by sowing where they are to grow, and thinning out unwanted seedlings. This is not generally done, however, partly because it pays to sow many of these crops early in the year, when outdoor sowings would be inadvisable, and partly because it is a waste of space to grow seedlings that develop slowly, as do most of these, in the main vegetable plot. It is better to use the nursery plot for their culture until they have, say, six or eight leaves, and then to transplant them to the main garden.