A productive blueberry bush develops a multi-stemmed structure that can become brittle and sprawling as it matures. When the canes of highbush varieties are heavily laden with fruit, they often bend or collapse, reducing the overall harvest and complicating the picking process. Providing physical and structural support is necessary to manage the plant’s growth, maximize fruit size, and ensure the longevity of the planting. The goal is to create a robust, upright framework that can handle the weight of a full crop.
Why Blueberry Bushes Require Support
Blueberry canes, particularly those of highbush varieties, are prone to breakage and collapse under the weight of a mature fruit load. Older canes are less flexible and become increasingly brittle, making them susceptible to snapping or falling outwards. When canes sprawl horizontally, the bush’s center becomes dense and the lower branches drag on the ground. This dense structure restricts air circulation and sunlight penetration, which leads to smaller fruit size and an increased risk of fungal diseases. Supporting the canes keeps the plant upright, promoting healthier growth and allowing pickers to access the fruit easily.
Implementing External Support Systems
External support systems involve physical hardware installed to immediately manage the weight and shape of the bush.
Three-Stake Corral
One simple method is the three-stake corral, where three durable stakes (such as galvanized metal posts or wooden stakes) are driven into the ground around the perimeter of the plant. Sturdy material, like polypropylene cording or thick twine, is then wrapped around the stakes at two or three different heights to contain the sprawling canes.
Wire Cage
For a more permanent solution, a wire cage can be constructed using heavy-gauge wire mesh. A section of this wire is rolled into a cylinder slightly larger than the mature bush and secured with metal clips or ties. This caging is effective for highbush varieties, offering all-around support that remains in place year-round.
Trellising
Trellising is another option, particularly for rows of plants, utilizing sturdy end posts and tensioned wire running down both sides of the row. This method keeps the fruiting wood upright and organized, improving canopy management and harvest efficiency.
Structural Pruning for Cane Renewal
Pruning is a long-term, internal support strategy that encourages the growth of stronger, more productive canes. The fundamental goal is constant cane renewal, systematically removing older, weaker wood to stimulate new, vigorous growth from the crown. Canes older than six to eight years become less productive and more brittle, so removing them redirects the plant’s energy toward creating new, structurally sound stems. Growers aim for a balance of 10 to 15 canes of varying ages within the bush. Each year, the oldest two or three canes should be cut completely back to the ground level during the dormant season. This removal encourages the production of new canes, which are naturally more upright and flexible, and will carry the heaviest fruit loads without collapsing.
Support Needs by Blueberry Variety
The type of blueberry cultivated directly influences the necessity and method of support required. Northern and Southern Highbush varieties require the most substantial support due to their brittle wood and tendency to reach six to eight feet. They are ideal candidates for permanent wire caging or the three-stake corral system. Rabbiteye blueberries exhibit a vigorous and upright growth habit, often reaching ten feet or more if left unpruned. While structurally stronger than highbush types, they benefit from regular structural pruning to maintain a manageable height and prevent sprawling. Lowbush and Half-High varieties are significantly smaller, rarely exceeding three feet, and seldom require external physical support.