How the calendar is built

Each crop has timing rules relative to your last spring frost (for spring planting) and your first fall frost (for fall crops), taken from widely used U.S. Cooperative Extension planting calendars. We place those windows on the calendar using your frost dates and the frost risk you choose above. Changing the risk to 10% shifts spring planting later and fall planting earlier.

Tips for using it

Sow fast crops such as lettuce, radish and bush beans in small batches every two to three weeks across their window for a steady harvest.
Soil temperature matters as much as frost: beans, corn, squash and melons rot or sulk in soil below about 60°F.
Fall crops are timed so they mature before hard frost; kale, collards, spinach and carrots get sweeter after a light frost.