Cutoff for major cuts on Mature Sweet Cherry Trees

Asked September 18, 2019, 3:17 AM EDT


It is September 18th and I have a very large sweet cherry (Variety Unknown - possibly Bing) that needs to be topped and trimmed as much as possible (I plan on removing the top 25% of the tree). The research I have done so far is telling that when making major cuts to sweet cherry trees, it is best to do it in summer-to-late summer so the tree has a better chance to heal without getting infected.

Also, it has rained the last 3 days in a row, but we have a window of decent daytime temps (above 70 degrees) and little to no rain forecasted in the next week.would you say it is too late or risky to make these major cuts now?

I was thinking about waiting until the tree goes dormant, also, but I am reading that making major cuts in late winter/early spring can invite infections like bacterial canker... What would you recommend in this case?

Washington County Oregon

1 Response

Pruning cherries, or any fruit tree for that matter, is of paramount importance. The primary reason for trimming cherry trees is to ensure the most optimal access to sunlight. Cherry tree pruning allows for aeration, allowing light channels to penetrate the tree, thus better fruit set, ease of harvest and the ability to battle or thwart disease.

So in essence, when you trim a cherry tree back, it will be allowed to develop a proper form, yielding higher quality fruit earlier in its life and remain healthier overall. Trees that have been improperly pruned or trained tend to have upright branch angles which may lead to limb damage under heavy fruit production.

The rule of thumb when pruning fruit trees is to do so when the tree is dormant during the winter. Cutting back sweet cherries is an exception to this rule. Sweet cherries are more susceptible to fungal and bacterial diseases, especially on recently cut limbs, so it is best to prune them in the late summer. Keep in mind that summer pruning reduces the tree’s energy for fruit production as well as its growth, so this should be minimal using only thinning cuts. Thinning cuts are those which remove an entire shoot, branch or limb up to the point of its origin and do an excellent job of opening up the canopy.

The number one task in cherry tree pruning care, actually prior to pruning any bearing tree, is to sterilize your pruning tools. This is to prevent the potential spread of disease from other plants to the cherry. You can wipe the blades down with rubbing alcohol and a rag or mix a solution of one part bleach to nine parts water and then rinse with clean water and dry.

Early spring is also prime time for pruning young cherry trees, shaping and training the young tree before it blossoms. Pruning should begin as buds emerge, but wait until all chance of extreme cold temperatures have passed to avoid possible cold injury, as younger trees are more susceptible to this. Mature cherries can be pruned in early spring too, or after they bear fruit.

Once the tree is three years old, it’s time to promote outward growth by pruning out new vertical limbs. At this point you will need loppers or pruning saws, not shears. Again, clean the tools prior to use. Also, prune out any dead or diseased limbs and dead fruit. Cut back any suckers at the base of the tree. Remove any crossed branches.

Cherries are prone to disease, so be sure to clean up all the discarded remnants. Also, cover all cuts with a fungicide like a fixed copper to fend off disease.

In summary, when you prune cherries, remember your goal. You are trying to create a tree that is well balanced, open and manageable, as well as aesthetically pleasing. There is no real science for pruning fruit trees. Some of it is trial and error. Look at the tree carefully and try to envision it as it will look when leafed out in the summer and eliminate any shoots that seem too closely spaced.

Hope this helps!