While the end of the garden season has basically flown past us with a flash of frost and freeze, there are still some things you need to do to prepare your garden for winter. Fruit trees and shrubs are no different, as there are some things you should do or prepare to do before the dead of winter arrives.
Clean up to reduce pests
While it is always a good idea to keep the garden neat and tidy to reduce insects and diseases, it is doubly important for fruits since many of those pests can damage or destroy your crop. Leaving debris such as dropped leaves and fruit provide ideal overwintering sites for those insects and diseases. Cleanup is especially important if you’ve been having issues or noticed signs of disease, such as spots on leaves and fruits or damage to leaves, fruits, or stems. Even if you haven’t observed these signs, leaving debris over winter can be just what those pests need to get a foothold on your plants next year.
Simply raking up leaves and fruits goes a long way to preventing these pests. If there are no current signs of disease, adding them to your compost pile is fine. If you do see diseases, the best solution is to remove them from the property – put them in yard waste bags for pickup if you’re in the city or bag them up for trash, bury, or burn them if you are in a rural area.
Sometimes fruits that have been affected by disease may dry up and stay on the tree or shrub. These are referred to as fruit mummies, and should definitely be removed during the winter to limit disease spread.
When to prune?
This is one of the most common questions we get with fruit trees, and the answer is….not yet. For most landscape trees and shrubs, early flowering plants would be pruned after flowering, but the optimal time for fruit tree pruning is late winter, just before dormancy breaks. This would be in the late February to March time frame.
While you can technically prune them any time during dormancy, it is best to wait until the worst of winter is over, that way if there is winter damage it will more likely be on parts that you want to remove rather than what you want to save. Plus, you’ll be able to remove winter damage when you do the regular pruning rather than having to prune twice.
The one exception to this rule would be for any part of the tree or shrub that is severely diseased or damaged. Don’t wait to remove those, as they can allow diseases to spread or become entry points for disease organisms and insects. Prune them out any time it is needed.
For a pruning how-to, check out this publication from UC Davis.
There are a few things you can do in winter to help prevent or control diseases and insects that may be plaguing your fruiting plants. One effective preventative for insects is the application of dormant oil in the late winter. This is a refined oil that, when sprayed to coat the tree or shrub, will smother out insects hibernating on the plant during winter. This is a very low-toxicity option for controlling pests, and can be done organically.
If your plants have been suffering from fungal or bacterial diseases, an application of a multipurpose fruit tree spray, sometimes referred to orchard spray, can help reduce diseases in the coming season. There are different formulations for different diseases, and some are as simple as a lime and sulfur combination or a fixed copper solution.
For specific diseases and spray schedules, check out this guide to managing pests in the home orchard from Purdue Extension.
Photos via: NCSU Fruit Tree Update Blog