We've all done it: Buy potatoes at the store or farmers' market, put them on the counter at home, and forget about them.
You recall your potatoes, but they've been busy and have sprouts. So why do potatoes sprout? When are they too far gone?
About 68 degrees F is when potatoes sprout. Your house's steady temperature confuses potatoes into believing it's spring and time to sprout.
Potato tubers retain surplus nutrients until spring, when they transform them into energy and sprout.
Sprouted potatoes contain solanine, which can be harmful. Potatoes and other nightshades like eggplant, tomatoes, and peppers naturally create solanine, which is hazardous in excessive amounts.
Dormant potatoes don't have solanine issues. However, improper storage and growing circumstances cause potatoes to produce solanine in their sprouts.
As potatoes sprout, their nutrients are converted into sugar, reducing their value. Leave them alone and they'll shrivel and be dangerous to eat.
You can consume sprouted potatoes that are firm, have little sprouts, and don't wrinkle or shrivel if you trim out the sprouted parts and soft spots.