Pruning is a foundational practice for cultivating healthy and productive sour cherry trees. When performed correctly, this horticultural task supports the tree’s vigor and enhances its ability to produce fruit.
Why Prune Sour Cherry Trees
Pruning sour cherry trees offers multiple benefits for their health and productivity. It improves fruit yield and quality by promoting better light penetration and air circulation throughout the canopy, encouraging robust fruit development. Pruning also maintains tree health by removing dead, diseased, or damaged branches, which can become entry points for pests and pathogens. Shaping the tree allows for easier harvesting and ensures a balanced, strong structure.
When to Prune Sour Cherry Trees
The optimal time for pruning sour cherry trees is during their dormant season, specifically late winter or early spring before bud break (November to March). Pruning then minimizes tree stress and allows wounds to heal promptly as new growth begins, reducing disease risk. Light summer pruning, performed after harvest (early August to late September), can be beneficial for maintenance, such as removing water sprouts or for light shaping. Avoid pruning in the fall, as it can stimulate new growth vulnerable to winter damage.
Essential Pruning Tools
Having the right tools is important for effective and clean pruning. Hand pruners are suitable for branches up to 1/2 inch in diameter. Loppers provide leverage for branches between 1/2 inch and 1 1/2 inches. A pruning saw is required for branches larger than 1 inch. Ensure all tools are clean and sharp to make precise cuts and prevent disease spread. Sterilize tools with a one-part bleach to nine-parts water solution to eliminate potential bacteria, fungi, or viruses.
How to Prune Sour Cherry Trees
Sour cherry trees benefit from an open vase shape, promoting optimal light and air circulation. To establish this, make a heading cut on the young main trunk, encouraging lower branching and creating foundational scaffold branches.
Remove dead, diseased, or damaged branches back to healthy wood whenever observed. These cuts prevent the spread of decay and disease.
Thinning cuts remove entire branches back to their origin, improving light penetration, air circulation, and fruit development.
Heading cuts shorten branches to encourage branching or control tree size and shape. Cut about a quarter-inch above an outward-facing bud at a 45-degree angle to promote outward growth. Remove crossing or rubbing branches, as they can create wounds where diseases enter and prevent structural issues.
Remove suckers (shoots from the base or roots) and water sprouts (vertical shoots from branches). These unwanted growths divert energy from fruit production and contribute to canopy density. Always cut just above a branch collar or a bud, avoiding stubs that hinder healing and invite pests or diseases.
Common Pruning Mistakes to Avoid
Over-pruning can stress the tree and reduce fruit yield; remove no more than about a third of the previous year’s growth. Pruning at the wrong time, particularly during active growth, can make the tree more susceptible to disease. Leaving stubs after cuts invites pests and diseases, as these stubs do not heal properly.
Making flush cuts, which are too close to the main trunk or branch, can damage the branch collar important for wound healing. Not using sharp or clean tools results in jagged cuts, making the tree vulnerable to infections. Removing too much fruiting wood, especially on sour cherry varieties that bear fruit on one-year-old shoots, can significantly reduce the harvest.
Post-Pruning Care
After pruning, clean up all removed branches and debris from around the tree’s base. This removes potential hiding spots for pests and diseases. If the soil is dry, watering the tree can help reduce stress and support recovery.
Monitor the tree for any signs of stress, disease, or pest infestation. Wound dressings are generally not recommended for cherry trees, as they can trap moisture and pathogens, hindering the natural healing process.