Raspberry bushes, which are technically canes, are a popular fruit for home gardeners. These plants grow tall and produce fruit on flexible, biennial stems, leading many new growers to question whether they require physical support. Providing a structure for your raspberry canes is a simple yet effective practice that directly impacts the health of the plant and the quality of the fruit. Understanding the growth habit and fruiting types helps implement the best system for maximizing berry yield.
The Necessity of Support
Most raspberry varieties benefit significantly from a support system, as their natural growth habit is not well-suited to standing upright when heavily laden with fruit. Raspberry canes are flexible and can reach heights between six and eight feet, becoming top-heavy when carrying a substantial crop. Without support, these canes often bend or fall over, creating a sprawling, disorganized patch.
Allowing the canes to flop onto the ground creates several problems, including increased susceptibility to disease. When canes and fruit rest on the soil, air circulation is reduced, leading to a moist microclimate that encourages fungal issues, such as gray mold (Botrytis). Keeping the canes upright and separated improves airflow, which helps foliage and fruit dry quickly after rain or irrigation. Supporting the vigorous growth also helps contain the plants within a manageable row, making pruning and harvesting much easier.
Understanding Cane Types
The type of raspberry determines the timing and extent of the support required. Red and yellow raspberries are classified into two main categories based on their fruiting pattern. Knowing which type you have is important, as their pruning and support needs differ.
Floricanes
Floricanes are the second-year canes of summer-bearing varieties, producing fruit early to mid-summer. These varieties need a permanent, robust support system because they grow tall and must survive a full winter before bearing their heavy load of fruit. Floricanes are typically pruned only after they have fruited, leaving the new first-year growth (primocanes) to be supported for the next season’s harvest.
Primocanes
Primocanes are the first-year canes of ever-bearing (fall-bearing) varieties that produce a crop in the late summer or autumn on the tips of the current season’s growth. While shorter primocane varieties may need less initial support, they still benefit from structure as they grow tall and the weight of the autumn crop pulls them down. If an ever-bearing variety is pruned down to the ground each winter for a single fall crop, a simpler, less permanent support can be used.
Methods of Support
The most effective support systems for home growers use a simple post-and-wire setup to contain the canes in a narrow row. For summer-bearing floricanes, the Post and Wire System is the standard method, involving sturdy end posts driven deep into the ground. Horizontal galvanized wire is run between the posts, usually at two heights, such as three and five feet. The canes are then tied directly to these wires with soft twine or plant ties.
For both floricanes and primocanes, a simple Hedge or Corral System provides excellent containment without requiring individual tying. This method uses two parallel wires or lengths of twine running down the row, held apart by short crossbars attached to the support posts. The canes grow up between the parallel wires, which keeps them sandwiched upright and prevents them from sprawling outward. This system is practical for managing vigorous growth and allows for easy access during harvest.