Cooperative Extension at Highmoor Farm

Prune Your Blueberries!

Why?

Highbush blueberry bushes should be pruned every year to produce regular crops of good quality fruit. Good pruning opens up the bush to more light and air movement, which will reduce disease problems. It also improves berry flavor and size, and encourages earlier ripening.

When?

Prune the plants when they are fully dormant, in late winter or early spring. Here in Monmouth, Dr. David Handley usually prunes in March, when the snow has receded enough to allow cutting canes back to the base of the plant.

How?

For young bushes less than three years old, just cut out any dead branches and weak, spindly growth.

Mature blueberry plants (4 years and older) should have six to ten healthy canes coming up from the base of the plant, ranging in age from one to six years old. The canes will vary in height from 4 to 6 feet, depending on variety. Each year prune the plants as follows:

1. Prune out any weak, low-growing or diseased canes.
2. Prune out any canes that are more than six years old (these are usually the thickest canes, with gray, peeling bark). Older canes are less productive and should be pruned out in favor of younger, more vigorous canes. The most productive canes on a blueberry bush are three to five years old. Cut the old canes back to ground. Leave six to seven vigorous two- to five-year-old canes and two or three one-year-old canes per bush.
3. Now move into the upper part of the plant and trim out any weak branches that have no vigorous new shoot growth on them, especially those in the center of the bush that are likely to be shaded. Fruiting shoots that grew out last summer and are typically green or reddish in color and vary in length from two to ten inches. They have swollen teardrop-shaped fruit buds near the tip, and smaller, pointed vegetative buds towards the base. Each fruit bud will produce a cluster of about six flowers in the spring. Trim out the shorter, weaker shoots, especially those less than six inches in length.

That’s it! This should leave you with a bush with about ten canes, ranging in age from one to six years old, each with several branches that have strong fruiting shoots on them. Following this method of annual pruning will encourage strong new growth, high quality fruit and fewer pest problems.