When to harvest sweet potatoes

Harvest sweet potatoes 85 to 120 days after planting, or by the time frost kills the vines, since the roots keep growing until then.

• Check the root size after 80 to 85 days, because the roots don't stop growing and can start to split when overgrown.
• If the vines are exposed to frost, dig the roots immediately because decay in dead vines moves into the roots.
• The tuberous roots should be harvested by the time frost kills the vines or soon thereafter.
• Chilling injury to the roots happens when soil temperatures drop to 50°F or lower, which can cause internal decay in storage.