Days to Maturity Chart: When to Plant for Fall Harvest

A days to maturity chart is a countdown, not a start date. You pick the harvest. Then you count backward.

Planting by the calendar is the common miss. "We always sow lettuce the first week of March" works once, in one year, for one market. It does not work for a fall CSA box, a Saturday market, or a buyer who wants heads on October 10. The harvest date is the constraint. Sow date is the remainder.

What to subtract

Field days come off the harvest date first. That is days to maturity from the field set, not from the day the seed hit a tray. If the crop is transplanted, nursery lead comes off next. Germination is inside the nursery lead. It is not a third block you add on top.

Salanova Butterhead shows the split. Days to maturity from the field is 55 days. Nursery lead is 24 days. Germination is 5 days. Cell tray is 128s. Occupancy, once it is in the ground, is 65 days, because holding runs 10 days past first cut.

The sheet's own season lines up. First harvest 2026-04-28 minus 55 days is 2026-03-04, the first field date. That date minus 24 days is 2026-02-08, the first greenhouse sow. Same cultivar. Same subtraction. Fall uses the same steps with a longer field clock.

Fall is not spring with a later month

Short days slow the crop. The sheet already carries the factor. Salanova Butterhead fall photoperiod is ×1.15. Bolero Nantes is ×1.1. French Breakfast radish is ×1.2. Corvair spinach is ×1.25. Sun Gold tomato is ×1. A fall sow that copies the spring interval will be late by that factor. The planner applies it when you count back from the market day. You do not add a folk-rule week and hope.

Bolero is the clean fall root example. Direct seed only. Germination is 12 days. Days to maturity from the field is 75 days. Holding is 21 days. Occupancy is 96 days. Four successions fit, every 21 days. A fall market date has to clear germination, 75 field days, and the ×1.1 stretch before frost ends the window. If the remainder lands after your last safe field date, that harvest is already lost. Sow earlier, or drop the date.

The chart is per cultivar

A single "lettuce: 55 days" line is not a plan. Salanova is 55 days from field set, plus 24 days on the bench, plus a 10-day hold. Astro arugula on the same library is 32 days to maturity, direct, 5 rows. Provider bean is 50 days from the field, direct, 8-day germination, 18-day hold. Redwing onion is 110 days from the field after a 70-day nursery lead. Put those on one calendar without the nursery split and the onion misses by two months.

Holding is part of the date, not a bonus. Salanova's sellable window is 10 days. Bolero's is 21. French Breakfast radish holds 7 days and the sheet spaces it every 7 days, 12 times. Miss the sow and you do not "catch up" inside a 7-day hold.

Use the harvest you already sold

Write the market day. Subtract field days. Apply the fall factor if that market day sits in short days. Subtract nursery lead if the method is transplant. That date is the sow. The next market is a new countdown, not the same sowing stretched.