This section is from the book "Vegetable Gardening", by Ralph L. Watts. Also available from Amazon: Vegetable Gardening.
When the most intensive methods are followed, the rows are made closer together than when the crop is grown on a large scale. It is held by many growers that close planting necessarily results in smaller shoots, but this is not the case with skillful intensive gardeners. More space between rows is obviously required when high ridging is necessary to grow the white shoots, although French producers of white spears plant as closely as most American growers of green shoots. Wide planting is also favorable to convenient cultivating, and plants and roots will not begin to crowd so soon. Therefore the plantation should be profitable during a longer period of years. On the other hand, wide planting materially limits returns for several years, and for this reason there is some tendency to plant closer and make new beds more frequently.
Planting distances vary considerably in different sections. In the growing of white stalks, the average spacing in England is probably 16 inches by 4 feet; in France, 2x4 feet; in Germany, 3 1/2 x 4 feet; in the largest fields in California, 2 x 9 or 10 feet (on reclaimed land) ; in New Jersey, 2 x 5 1/2 feet; in New York, about 2x5 feet. In New Jersey green asparagus is usually grown 2 or 2 1/2 x 5 feet; at Concord, Mass., 2x4 feet; in Pennsylvania, 2 x 4 or 4 1/2 feet. An extensive grower in Philadelphia County, Pa., plants 4x4 feet, while an intensive grower at Cleveland, O., plants 1x3 feet. Peter Henderson recommended 9 inches by 3 feet.
 
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