If you have a blueberry bush, your goal is probably to get the most blueberries possible. To maximize your harvest, pruning in the early spring is important.
Homegrown New Hampshire host Emma Erler, lead horticulturist with Kirkwood Gardens, says the philosophy behind blueberry pruning is to constantly remove the older, decreasingly productive canes (or stems) and forcing new canes to take their place. The plant is continually replacing old canes with new ones, while the majority are in a productive, intermediate stage.
Pruning is best accomplished toward the end of the dormant season, some time in spring. In late March and April, the flower buds are easily recognizable since they are larger and fuller than the leaf buds.
If your blueberry plants are recently planted, Erler says you should remove all fruit to force vegetative growth of the plant.
To prune in following years, she says to follow the instructions below:
1. Remove dead, diseased, damaged canes and any small, spindly canes that lie on the ground.
3. Thin canes, trying to maximize light conditions inside the plant by removing the centermost canes (which block sunlight).
4. Healthy, mature plants should produce 3-5 new canes a year. If this isn’t happening, check your fertilizer program, pH, and moisture levels.
5. Every year, select the best two to three new canes to keep and remove the rest.
6. After 5 years, begin removing the oldest canes while retaining the three best new canes.
7. Thin remaining canes by removing weak lateral branches and dense brushy twigs.
If your blueberry bushes haven’t been pruned in years, or ever, Erler says they can be rejuvenated over the course of three years.
In the first year remove one-third of old canes. In year two of your process, remove half of the remaining old canes. Remove the final third of old canes in year three. Spreading out the rejuvenation means you’ll still get fruit production while also stimulating new growth.
To provide ideal growing conditions for blueberry bushes, you need acidic (pH 4.5-5.4), well-drained, sandy loam improved with organic matter. Avoid sites that are extremely wet or dry. Use mulch to retain soil moisture, moderate temperature, and reduce weeds.
You can change your soil pH as necessary based on a soil test. Make things easy by using a fertilizer made for acid-loving plants. Apply shortly after buds break in Spring.
If you have a gardening question for Homegrown NH, email or send a voice memo to HomegrownNH@ NHPR.org.
See you in the garden!
Homegrown New Hampshire is a collaboration between Squam Lakes Natural Science Center and NHPR.
