Expert gardener’s tip: These methods work equally well for both English and black walnuts..
Air Drying
Air-drying your walnuts has two advantages: You can do it outdoors or inside and it’s suitable for any amount of walnuts.
Outdoor Air Drying
Set up an outdoor table in a shaded area with good air circulation and cover it with a single layer of walnuts; try to keep them from touching. To block moisture, drape the table with a tarp at night and during rain. Stir the nuts daily sun to get even air exposure.
Expert gardener’s tip: Robins, blue jays, woodpeckers and other strong-billed birds love to snack on walnuts. Plastic bird netting keeps them away.
Indoor Air Drying
To dry lots of walnuts indoors, any flat surface large enough to hold them will do. Besides tables, we suggest:
- Shallow cardboard boxes
- Seed planting trays
- Wire shelving units with mesh screens covering their shelves. Adding the screens eliminates the daily stirring requirement.
Put your drying surfaces in a cool, dry spot out of direct sun, such as an enclosed porch or an attic. Spread the nuts thinly over them and — if you aren’t using screens — stir them each day.
Mesh Bag Drying
Dealing with a small walnut harvest? Just put your walnuts into onion or other mesh bags and hang them in a dry, airy space. Shake each day to redistribute the nuts.
Expert gardener’s tip: Regardless of which indoor method you use, expect your walnuts to need at least two weeks to dry.
Oven Drying
If you’re short on time with a small harvest and an oven to spare for a couple of days, this is the method to use. Set the oven temp between 90° and 100°F (32.2° and° 37.7°C), spread your walnuts on shallow baking trays and heat them for 36 hours. Caution: If the temp exceeds 100°F, the nuts will shrivel.
Testing Your Walnuts
How do you tell when your walnuts are dry? Crack a few open and examine the kernels. If you find brittle membranes between kernels that snap sharply when bent, they’re ready. Waxy kernels with a sour flavor and strong aftertaste need more drying time.