In no essential respect does the treatment of the blackberry differ from that of the raspberry. The plant is a more rampant grower and should have more room. It also needs more careful pruning and pinching to secure best results. Six to 8 feet is the usual distance at which rows are made and 2 to 3 feet between the plants in the row. Prefer-ably, however, blackberries should be set in checks 6 by 6, so that cultivation may be given both ways.
As to pruning, the young shoots should be pinched when they reach a height of 3 feet to 3o inches. This can be done with the thumb and finger during the summer. Shortly after the pinching, lateral branches will appear. These should be pinched when they are 12 to i8 inches long, depending upon the variety. Some varieties bear their fruit buds close to the main stem, others farther out. This feature can be determined only by observation of the various varieties. As a result of this pinching, the main stems grow very stocky and the laterals strong and more or Iess rigid. They thus bear their fruit well up from the ground and there is no danger of the stems falling over when the crop is abundant. After fruiting, the canes that have borne should be as light as possible for the maturing of the young canes, which will bear the following season. Three to five canes are enough to allow to grow each year, de-pending upon the strength of the variety. Large-growing kinds should have the smaller number. The old canes should be removed from the plantation and burned. (See also Raspberry.)
In some places it is thought advisable to cover blackberries during the winter to protect them from freezing, but usually it is not necessary in ordinary climates where the above method of pruning is practiced. The winterkilling is largely due to immature wood which freezes. Well-ripened wood is rarely injured by frost except in very cold locations.
Among the best known varieties are Agawam, Ancient Briton, Early Cluster, Early Harvest, Erie, Kittatinny, Mersereau, Snyder, Taylor, and Wilson.