BLUEBERRY CULTURE 7 



When the cuttings have started to root, the latter part of June, ventilation 

 of the frames is started and is gradually increased until the sash can be removed. 

 The latter part of August, the amount of light given the cuttings can be gradually 

 increased by taking off the shades earlier in the evening and replacing them 

 later in the morning, until they can be left off altogether. 



The young plants may be left in the cold frame during the winter with some 

 hay, straw, or similar material placed over them for protection. In the spring 

 they are set in a nursery where they are grown for one or two years before they 

 are ready to put in the field. The nursery should be kept well cultivated, but 

 the cultivation must be shallow so as not to disturb the roots of the plants. 



Planting 



Planting should be done as early in the spring as the condition of the soil 

 permits. The plants are set five feet apart, in rows eight feet apart. So spaced 

 1,089 plants per acre are required. Each plant as received from the nursery 

 has the roots covered by a ball of earth which should be disturbed as little as 

 possible in planting. When the plants are set, the holes are dug large enough for 

 the roots to be placed without crowding and deep enough so that about one inch 

 of the stem will be below the surface of the soil. Under some conditions blue- 

 berry varieties may be self-sterile, or nearly so. Therefore, it seems best to 

 plant at least two varieties . They can be set in alternate rows if they are equally 

 desirable, but if not, at least every fourth row should be a different variety. 



Soil Management 



Blueberry plantings are usually kept under cultivation, which is started as 

 early in the spring as the soil can be worked and stopped about the middle of 

 August. Continued later than this it may cause late growth and make the 

 plants susceptible to winter injury. 



Since blueberries are shallow rooted, cultivation should not be deep, particu- 

 larly close to the plants. In recent experiments in New Jersey (2) cultivation 

 two to four inches deep between the rows gave better results than cultivation 

 one to two inches deep. They, therefore, recommend cultivation to an average 

 depth of three inches between the rows but no nearer to the plants than the ends 

 of the branches. To keep down weed growth close to the plants, they recom- 

 mend hand hoeing or very shallow cultivation with an acme harrow. This 

 agrees with experience in Massachusetts that some cultivation is necessary to 

 keep the soil from becoming hard and poorly aerated but that deep cultivation 

 close to the plants does more harm than good. 



Fertilization 



The blueberry, like most plants, responds to fertilization. Nitrogen generally 

 has the most effect on both growth and yield, but recent experiments in New 

 Jersey (2) indicate that a complete fertilizer is desirable because nitrogen used 

 alone causes an excessive shoot growth. 



Young blueberry plants are easily injured by too much fertilizer. No fertilizer 

 need be applied the year the plants are set. The first year after planting, a 

 small handful well spread out around each plant is enough. The next year a 



