Interactive planning tool

Seed-starting calculator

Work backward from transplant timing.

Work backward from transplant day.

Choose your expected last frost and the packet’s recommended indoor lead time.

CropLast expected frostWeeks before frost6 weeks

Illustrated growth sequence for tomato, from establishment through mature harvest.

Start tomato aroundMar 20, 2027Follow the packet for this variety, then adjust for your grow-light capacity and realistic outdoor planting date.

How to use the result

A plan is a starting hypothesis.

Confirm crop-specific guidance, compare the recommendation with current conditions, and revise when the garden gives you better evidence. Inputs remain on this page while you work but are not stored as an account or permanent record.