Planting, Growing, and Harvesting Plums
Growing
How to Care for Plum Trees
Watering
- Be sure to water the young trees heavily every week during the first growing season to help promote growth. Then, water regularly. It’s best to water the plant deeply at the soil line, then let the soil dry out (though not completely) and water again.
- If rain is lacking, water your tree well into mid-October to give it plenty of moisture through the winter months.
Fertilizing
- Do not fertilize young fruit trees until they have set a crop.
- Once established, fruit production requires regular fertilizing all year long. If there’s good fruit set, fertilize with one pound of calcium nitrate per tree or 1½ lb. 10-10-10. Cut back the nitrogen in fall and winter to avoid encouraging new growth in those seasons.
General Care
- Are you having pest issues? Talk to your local cooperative extension for natural solutions that work in your area.
- To help control pests and diseases, remember to prune your trees to keep them open. You can also mulch around the trees in the spring to help control weeds, but be sure to remove the mulch in the late fall so that no pests use it over the winter. You can also lightly cultivate the soil around your trees in late spring to eliminate any pests in the soil.
- In the fall, rake away all debris and fallen trees.
- To prevent winter injury: Consider a tree wrap or guard around the lower trunk, especially for a young plum tree.
- Keep an eye on the lower bark and branches for mouse or rabbit damage; if this could be a problem, you may need to install tree guards or fence in young trees with chicken wire for the winter.
How to Prune Plum Trees
When to Prune
- Prune in early spring or mid-summer to avoid infection. The best time for pruning is usually spring for young trees and mid-summer for established ones.
- Do NOT prune in the fall. Winter injury and infection may occur.
Thinning Fruit
“Thinning” is the process of removing developing fruit from a tree in order to increase the overall quality of the produced fruit and to prevent damage to the tree.
- Thinning is usually done about a month after blooming ends in the spring.
- Leave 2-4 inches between each fruit, removing those in between.
- Thinning helps to prevent branches from breaking under the weight of the fruit. If branches do break, prune them back to undamaged wood, ideally cutting back to a natural fork to avoid leaving stubs.
Pruning: Japanese Plum Trees
- If you have a Japanese variety, the best pruning method is to create an “open center” shape, where the central trunk is cut short and several large branches radiate outwards from it’s tip. In the summer of the first year, cut the vigorous shoots that form on the top of the tree by two or three buds. After about a month, check the tree. As soon as you have three wide-angled branches, spaced equally apart, cut back any other branches so that these three are the main branches. In the early summer of the second year, cut back the branches in the middle of the tree to short stubs and prune any shoots developing below the three main branches. After the third year, remove any shoots in the center of the tree to keep its shape.
- Japanese types require heavy pruning to help keep them in shape and to produce better fruit. It is also good to thin out the fruit on these types of trees. You should space the plums about 3 to 4 inches apart on each branch.
Pruning: European Plum Trees
- If you have a European variety, the best pruning method is to create a central leader. This shape features a central trunk with branches that spiral out every 5 to 8 inches, making sure that no branch is directly above another. The training for such a system begins in the early summer of the first year, during which time you should remove any shoots that form within 18 inches of the ground. The end result should resemble a Christmas tree.
- European types do not typically require fruit thinning because they do not produce as much fruit as Japanese types. However, the fruit on these types should be spaced about 2 inches apart on each branch.
For more pruning tips, check our spring pruning guide.
Types
- For a European type, try the ‘Stanley’. This semi-freestone type works great for the eastern, midwestern, and some of the northwest regions of the U.S. It is self-fertile, meaning no cross-pollination is necessary. It’s harvested in late August, producing medium to large plums with dark blue skin and greenish-yellow flesh and is great for cooking, canning, or eating fresh.
- For a Japanese type, try the ‘Satsuma’, which produces large, dark-red plums. This kind is good for eating fresh and canning because of its sweet taste.
- American hybrid trees, such as ‘Alderman’, ‘Superior’, and ‘Underwood’, are all popular choices. These trees combine the taste of the Japanese variety with the hardiness of the European variety. These types work well for regional extremes.
Cooking Notes
- Plums are great for making jams or jellies.
- Plums can also be stored through freezing or drying them (dried plums are prunes), learn how to dry fruit with a dehydrator.
Catherine Boeckmann
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This article does not describe how to prune or when to pick American Hybrid varieties. Which is what I have.
Hi S,
You should plan to prune your plum trees in late winter/early spring, after the coldest part of the winter has passed, but before buds break and new growth occurs. When pruning is done during the summer or fall, it can reduce dormancy and can potentially cause damage to your plum trees, especially when there is an early winter.
When pruning, start by removing and dead, damaged, or diseased branches. Then remove branches to allow for more light to penetrate, increase fruit quality, and encourage new branch development. You should also prune off suckers coming from the rootstock and vegetative water sprouts growing straight up from main branches.
Harvesting plums will take place in summer into fall (depending on your growing area). You should allow the plums to ripen on the tree as they will not gain sweetness once picked. One indicator is if you press on the skin and it is slightly soft to the touch. If you are unsure, pick one and try it to see what if the taste is to your liking.
Hope this helps!
I don't know the type of plum tree i have, but it's rather large and produces a lot of plums. We have this black fungus that keeps growing on the branches every year. We have tried neam oil and neam pesticide, which have not worked.
I purchased a Hollywood variety for my Seattle area home, and now realize I need a 2nd variety for x-pollination. The next closest location for the 2nd tree would be about 100' away. Is that too far for an effective x-pollination sibling?
Thanks
The recommended maximum distance between plum trees is 50 feet, but as long as there are plenty of pollinators in your area, 100 feet shouldn’t be too far. You may just end up with fewer plums than ideal—but that’s better than no plums!
My Stanley Plum Tree dropped over half its unripened fruit in early July and then dropped more in August. It does not appear diseased. Is that a sign of lack of fertilizer or hot weather? Or some other reason?
I have been having this same problem for the last few years. I have tried watering, 10-10-10 and citrus fertilizer to no avail.
My trees are loaded and when the fruit is about half size they begin falling off.
I am in mid S.C. And the trees are in full sun.
I am having the same issues with my two peach trees.
Any ideas of what I should do.
Best time to plant
That’s unfortunate. It’s unlikelly to be too much or too little fertilizer. Premature fruit drop is common among fruit trees; it’s Mother Nature’s way of reducing the load—especially if you do not thin the fruit load yourself (prune when plums are about 3/4-inch long, leaving 4 to 6 inches between remaining fruits). Weather could be a factor; high heat in early spring can stress the tree, and if conditions in general have been dry, the tree may not be well irrigated.
I'm in zone 4 and two years ago bought a home with two plum trees on the property. They are quite large, have lovely, fragrant blooms in early spring, but have produced no fruit at all. What could be wrong? The trees are healthy looking with no sign of pests or disease. Help?
