By Dr. Sandra L. Anagnostakis
Department of Plant Pathology and Ecology
The Connecticut Agricultural Experiment Station
123 Huntington Street
P. O. Box 1106
New Haven, CT 06504-1106
Telephone: (203) 974-8498 Fax: (203) 974-8502
Chestnuts usually ripen in early October, and fall free of the burs which open as the weather becomes colder. Nuts picked up off of the ground should be kept cool and dry for a day before storing. If the animals always beat you to the nuts that fall to the ground, you may cut the unopened burs in early October. Keep the burs cool (in a root cellar for example) and they will open when the nuts are ripe. The nuts can be removed from the burs using heavy rubber gloves.
The chestnuts should be stored in slightly dampened sphagnum moss in a plastic bag, closed with a twist-tie. Keep the bags in a refrigerator at about the level of the vegetable crisper, so that there will be no danger of freezing.
If larvae of the chestnut weevils eat their way out of the nuts and bags, there is no reason to discard the nuts. The larvae are not likely to have killed the nuts as they emerged.
Chestnuts start to germinate as soon as they have had enough dormant time, and roots will be seen coming out of the nuts. This usually happens in early February, but will depend on the temperature of your refrigerator. They can be kept in the cold until mid-May for outside planting, or planted in potting mix (not soil) in containers. The half-gallon cardboard containers from milk make excellent pots. Poke a few holes in the bottom for drainage, fill with potting mix, carefully place the germinated chestnut in the top and cover with about one inch of potting mix. Grown on a sunny window sill, they will be foot-tall trees when it is warm enough to plant them outside (mid-May in Connecticut).
When planting seedling chestnuts outside you must find the old nut shell (still clinging to the root) and carefully twist it off. Animals will pull up the trees looking for the nut if you donít do this.
If you have tree-protector tubes available, you may plant the seed directly in the ground when it is warm enough, and place a tube (firmly staked) around it to protect it from predation.
Trees start best with a little shade. Never fertilize trees when planting: this encourages leaf production, and they first need to make roots. Make sure that they have plenty of water during dry spells. If you keep a coffee can near them you can gauge the amount of every rainstorm. If the trees have not gotten one inch of rain in a week, give them an inch of water (set up a sprinkler and check the coffee can). They need to be watered as long as they have leaves (during the growing season).
In their second season outside you may start fertilization, but donít apply fertilizer later than late July. Keep weeds away from the base of the trees to reduce their competition, and to keep people with lawn mowers and weed-whackers from damaging them. Chestnuts can grow very rapidly, and under good conditions Chinese trees will have nuts when about 5 years old, American trees at about 8 years old.
Chestnut trees grow well in Connecticut and can be grown from seed or purchased as seedlings or grafted trees.