Growing potatoes for the first time? Wondering when is it time to dig them up? The answer may depend on whether you’re growing potatoes to enjoy with a summer meal or for long term winter storage. Here are our tips for digging potatoes.
New potatoes are intentionally harvested early for their smaller size and tender skins. Any variety of potato can be harvested as a ‘new’ potato, as the plant hasn’t yet reached maturity. The smaller size potatoes are coveted for their moist substance, and they’re often cooked, steamed and served whole. Harvested early, new potatoes don’t store well – their thin skins allow the evaporation of their interior moisture. When harvesting new potatoes, you’ll want to consume them shortly after digging them.
If you decide to harvest new potatoes, keep in mind the plant as it is lifted from the soil is often forfeited. The plant is unlikely to recover, and there will be no mature sized potatoes for winter storage. Harvest new potatoes in early to mid-summer, approximately 2-3 weeks after the plants stop flowering.
Potatoes for winter storage are harvested once the plant is fully mature, at the end of its growing season. You’ll see the plant’s foliage begin to yellow starting with the lower base leaves, and then progress up the stems. When the plant has completely yellowed and withered wait another 2 weeks before digging to allow the skins to thicken. The key to good storage for potatoes: thick, unbroken skins which reduce the loss of moisture.
Choose a dry, sunny day to dig garden potatoes, when the soil is also dry. If the soil is moist or wet, let the tubers air-dry as much as possible before storing them away in sacks or baskets. Dig with care to avoid piercing or bruising the potatoes and damaging their skins. Feel around through the soil with your hands to uncover and discover the tubers. If you are growing your potatoes in a grow bag you can simply dump the contents onto a tarp laid out over the ground.
Keep freshly dug potatoes out of the sunlight. Place them under the cover of burlap or a tarp until they are ready for long term storage. The ideal temperature range for harvesting potatoes at the end of their season, is 13-18°C (55-65°F).
Store potatoes in a dark location in cooler, moist temperatures of 4-7°C (40-45°F). A cold cellar is ideal, but potatoes can also be stored in paper or burlap sacks in a cool garage or shed. The refrigerator should be off limits to potatoes. Avoid storing tubers next to onions and apples too, as the gases emitted by these foods will cause potatoes to spoil. Ethylene gas is harmless to humans, but not so for your potatoes. Check on stored potatoes regularly and remove any that have started to turn. Finally, avoid washing potatoes until you are ready to use them, as washing potatoes shortens their storage life.