Cold Frame Calculator — How Many Cold Frames Do I Need
Calculate cold frame size and capacity for hardening off plants.
How We Calculate This
This calculator estimates that a standard cold frame holds approximately 20 seedlings in individual pots.
The number of cold frames needed is: Seedlings / 20 (rounded up). Adjust if your trays hold more or fewer pots than average.
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.