Almost any vegetable can be grown in raised beds or in containers, but even in raised beds some system of rotation should be practised. In some market gardens a four crop rotation is followed, with potatoes being the first crop, followed by, peas and finally greens. However, potatoes are not grown in a garden, so a three crop rotation is best adopted: greens, roots, and legumes, with other crops such as onions slotted in as a fourth year crop if desired. The reason for rotation is to avoid build-ups of nutrients, pests and diseases, since each crop requires different nutrients – greens need plenty of nitrogen, while crops need phosphates.
With raised beds and large ‘flats’ the garden can be divided into sections and a simple rotation adopted. But although rotation is important, it is often impractical, especially with window boxes, or just a few tubs.
Small Scale Vegetable Growing
Even in a window box, vegetables can be grown by planting two or three rows of plants and having a large plant at each end. Such a window box could have a tomato plant at each end, and rows of carrots, radishes, lettuce or peas, with an edging of chives or parsley. The choice is open, but remember that a window box should have a soil depth of about 25cm/ lOin, and always choose dwarf or small cultivars such as ‘Tom Thumb’ lettuce and ‘Little Marvel’ pea. For example, there is no point in growing ‘Gradus’ pea as it is 1.2m/4ft tall.
When using a tub, plant a tomato or pepper in the centre and then grow concentric rings of other crops, or devote the whole tub to salad crops. Alternatively, a tub can be devoted
to one vegetable, such as tomatoes or aubergines or eggplants. The soil mix in the tub must be rich enough tocrops throughout the growing season, so prior to or planting, incorporate plenty of organic matter, such as peat or garden , plus a general purpose fertilizer at 250g/8oz per sq.m./sq.yd.
Crops to Grow
It is important to stress that only certain cultivars of each vegetable are suitable. Careful selection is required when studyingcatalogues, or packets of seed in garden centres, and mammoth or exhibition strains of most crops should be avoided. In all gardening the -run is limited and space is at a premium. Crops such as rhubarb and asparagus should not be attempted unless major sacrifices are made.