The garden should be near the house and away from trees. If it's some distance away from the house, it will not be as well looked after, nor will most use be made of vegetables grown. Vegetables near trees cannot get full sunshine; even more important, tree roots will rob them of water and fertilizer they need to do their best.
If you can, move the garden spot every 10 years or so to help keep down diseases. Proper rotation and use of disease-resistant varieties will help, but sooner or later the old garden spot becomes so full of various disease spores and nematodes that you cannot grow a good crop of many vegetables without use of special soil fumigants.Soil should, of course, be well drained. Few vegetables can stand "wet feet." A sandy loam with a clay subsoil is best. Heavy clay soils may be made quite suitable by adding heavy quantities of stable manure or compost, or by turning under cover crops, preferably legumes such as vetch, clover soybeans.
