When your potato plants begin to die back, it’s a sign that you can start to dig them up for winter storage. You can leave them in your garden until the plants die back almost completely, but they don’t tolerate cold temperatures or frost.
Before you dig up the entire patch, dig up one plant and test its tubers. If their skins are thin and easily rubbed off, it’s too early to harvest. The skins need to be thick and firm so that the potatoes will cure properly.
If you can, avoid harvesting your potatoes when the soil is damp. You want the potatoes to be as dry as possible.
- Insert a shovel or garden fork at least a foot away from the plant, dig down about a foot, then carefully lift the plant up.
Some varieties of potato plants develop tubers right under the plant, and others develop them quite far away, so you may need to adjust where you shovel to avoid impaling–or overlooking–any tubers.
The tubers should become obvious as the roots are lifted and the dirt is loosened. You may need to dig around the plant several times to find all of your treasures.
- Sort your potatoes according to size, type, and condition. Knock off any clods of dirt that cling to them, but don’t wash them.
- Set aside any damaged potatoes; you will need to use these as soon as possible.
- Lay the rest of the potatoes out to cure in a relatively warm (~8-16 degrees Celsius) but dry place, for a week or so, until the skins have hardened. I arrange mine on newspaper atop a hardwood floor in a room that gets some sunlight but is not too bright or hot. If potatoes are exposed to too much light, they may turn green.
- After the potatoes have dried and their skins have hardened, arrange them in baskets, mesh bags or any containers in which the air can circulate around them (but light cannot get to them), ensuring they don’t touch each other. At the time that you are packing them into their baskets, you may be able to gently brush off some more of the dirt that clings to them.
- Place them in dark, dry, cool (~4 degrees Celsius) location such as a root cellar or cold room.
- Periodically go through your stores to check for, and remove, any potatoes that have rotted. One rotten potato can spoil others!
- Enjoy! Potatoes can last up to a year if stored properly, but refer to the guidelines for the specific varieties you’ve planted for specific expectations regarding longevity. I use small potatoes before large potatoes, and red-skinned potatoes before white and yellow-skinned potatoes.