Things You'll Need
Soil testing kit
pH testing kit
Pruning shears or pruning saw
10-10-10 fertilizer or compost
Persimmon trees are easy to grow and aren't bothered by pests or disease. Assuming your persimmon tree is hardy in your growing zone and has been planted at the proper depth, in full sun and well-drained soil with a pH of 6.5 to 7.5, it should live for 15 to 20 years. Some early fruit drop is to be expected, especially in heavy fruiting years. However, if your persimmon tree is consistently dropping fruit and its leaves are yellowing, you may be over-fertilizing or over-watering your tree. Soil testing and adjusting water drainage problems can help your tree recover, although it can take up to two years for your tree to completely recover.
Caring for a dying persimmon tree
Cut dead and dying branches back to live wood. Remove overgrown vegetation and weeds under the canopy. If you have mulched the tree, make sure the mulch is at least two to three inches away from the trunk.
Check the drainage around your persimmon tree. Dig a hole just outside the drip line that is about three feet deep. Fill the hole with water. If the water drains in 24 hours or less the drainage around your tree is fine. If it takes 24 to 48 hours for the water to drain, the drainage is slow, which water logs the roots. Water-logged roots will rot, causing the tree to die. You will need to create a drainage system around the tree that directs excess water away from the roots.
While excess water can cause your tree to die, not enough water can also kill your tree. Persimmon trees are drought resistant, but a prolonged drought may cause the tree to die. Persimmon trees need approximately 36 inches of water a year to survive. If the area you live in is in a drought, you will need to give your persimmon tree two to three inches of water a week.
If water is not an issue, you may be over-fertilizing your persimmon tree. Persimmons should be fertilized once a year, in late winter or early spring, with a balanced commercial fertilizer like a 10-10-10 blend or compost. If you have over-fertilized, keep your tree watered and plant a shallow-rooted, easily removed ground cover like vinca under the canopy of the tree to help remove some of the excess nitrogen. Do not apply fertilizer the following year. Wait until your tree starts to recover before removing the ground cover and applying fertilizer.
Persimmons do well in poor soils, but lack of nutrients will cause branch dieback, fruit drop, and yellowing leaves. Do a soil test and check the pH of the soil under the canopy. Try to disturb the roots as little as possible. You can buy soil and pH tests in most garden centers or send soil plugs to your local extension office for a more complete soil profile. You will need to wait until late winter or early spring before applying fertilizer or compost. You can correct the pH at any time.
Persimmon trees do not like to be transplanted, it is better to plant them in the right location rather than trying to move them if they aren't thriving.