A rough scheduling aid for tracking heat accumulation in your garden. We don’t have live weather data built in — enter each day’s high and low from your weather app, and this calculator keeps the running total for you.
Default 50°F — the standard base for most warm-season crops. Corn and many vegetables use 50.
Running total: 0 GDD
Your total vs. crop targets (approximate)
Targets are approximate published ag-extension values — varieties and microclimates shift them.
How it’s figured
GDD per day = max(0, (high + low) ÷ 2 − base temperature). The daily average is capped at the base: a day cooler than the base adds 0, never a negative. Your running total is the sum of each day’s GDD. Reference targets shown are approximate published ag-extension values.