Harvest planning tool
Days to maturity calculator
Use the number printed on a seed packet to estimate a maturity date. First confirm whether that packet starts counting from sowing, emergence or transplanting, then enter the matching date.
Seed packet calculator
Estimate a maturity date
Step 1
Find the packet's starting point
“Days to maturity” does not use one universal starting point. A transplant crop may count from the day it goes outdoors, while a direct-sown crop may count from seeding or emergence. Use the packet or catalog definition instead of guessing.
Step 2
Compare with fall frost
The optional frost field shows the calendar buffer between estimated maturity and an average first fall frost. Use the frost date calculator for a local historical estimate.
How to read the result
A positive buffer helps
More days before average frost provide more calendar room, but they do not guarantee suitable heat, light or moisture.
A date after frost is a warning
For a frost-sensitive crop, an estimate after the average first frost suggests choosing an earlier variety or revising the planting plan.
Harvest readiness is physical
Inspect the crop's size, color, firmness or other packet harvest signals. The estimated date only tells you when to begin paying closer attention.
Average frost is not this year's forecast
Historical frost normals describe probability, not a deadline. A damaging frost may arrive before or after the average date, and some cool-season crops tolerate more cold than warm-season crops.