Mulching - A layer of organic mulch 2 to 4 inches thick keeps the soil moist, and should take care of any serious weed problems. The mulch can be such material as chopped leaves, pine needles or wood chips. Because the tree is shallow rooted mulching is necessary. Avoid mulching with whole leaves because they mat together, preventing water from soaking into the soil. Peat moss makes poor mulch, because it draws water from the soil like a wick and is difficult to rewet when dry.
If you don t mulch, be careful with weeding tools, to avoid damaging the tree s root system. It s best to hand-pull weeds growing close to the tree. Hard-to-kill perennial weeds can be controlled by spot treating with a fatty acid soap herbicide or a glyphosate herbicide, both of which are biodegradable. If you splash the foliage with the chemical, rinse it off with water
Watering - Chestnuts don t usually need watering except when they re first planted, in time of drought, or in late fall before the ground freezes for the winter. If you want to water more frequently, give your trees 1 gallon of water twice a week. Older trees need watering only during severe drought.
In the fall when the nuts fall to the ground, you may wish to rake up those Chestnuts falling on to the sidewalk or driveway to avoid anyone s stumbling and falling because of them.
Pruning - Generally this tree wants to grow with multiple trunks and that is fine for many yardeners. You can, however, prune the young tree to grow on a single trunk with very little difficulty.
Fertilizing – Feeding these trees is optional, however if you wish to feed them Chestnuts need only one fall application of fertilizer such as commercial sludge, compost, or granular 10-10-10 fertilizer with a slow release form of nitrogen. Scratch granular fertilizer into the soil to 1-1/2 times the distance from the trunk to the tips of the branches (the drip line), and don t let fertilizer touch the trunk. Normally you will need about 1/2 pound of fertilizer for each tree with a trunk diameter of 1/2 inch at the base. For larger trees, use 1 pound for each inch of trunk diameter. Do not apply fertilizer when planting a tree, nor during the first season.
Chinese Chestnut trees do not require routine pruning. However, from time to time it will be necessary to trim wayward branches or cut out diseased or damaged limbs.