When Is a Chestnut Ripe?

Ripeness Indicator

• The fruit of a chestnut tree does not ripen all at the same time. Instead, it ripens over a period of 10 to 30 days starting from the end of August. If weather conditions have not been optimal for growth, this period can extend to five weeks. As the nuts ripen, they fall from the tree. They should not be manually removed from the tree like other nuts. According to the University of California Extension office, the fruit achieves over 50 percent of its total weight in the last two weeks before it falls. It also splits its burs before naturally falling. Never shake the tree to remove nuts as this causes a loss of immature nuts.

Nut Collection

• Since chestnuts are fully mature when they fall, collect them immediately. Inspect fallen nuts every other day for those that have split hulls or burs. Leave the nuts with unopened hulls as these are usually useless. Spread a heavy tarp under the tree and use thick leather gloves to protect against the spiny burs.

Separating Nuts

• Chestnuts are highly susceptible to mold if they are not separated immediately from the hulls right after harvest. Either use heavy gloves to remove the hulls or step on the nuts to help the nuts pop out. It is possible for the burs to resist separation from the nuts. In these cases, leave these nuts for a couple of days at 55 to 65 degrees F before trying to separate them again.

Storage

• Unless chestnuts are to be cooked within a couple of days of harvest, the Clemson Cooperative Extension recommends drying them properly. Create a tray with 1/2 inch mesh hardware cloth and spread the nuts in a single or double layer. Let the nuts air dry for several days to remove moisture and discourage mold. Nuts that are intended for fresh use are best dried to remove the astringent flavor of raw nuts. Store chestnuts in the fridge in sealed containers for up to several months and up to a year in the freezer.