GardenCalcs.uk
Succession Planting Calculator — Continuous Harvest
Plan sowing intervals for a continuous harvest throughout the season.
How We Calculate This
The sowing interval follows RHS Successional Sowing advice — small batches every 2-3 weeks for a continuous supply (faster croppers like radish and beetroot at the 2-week end). Total sowings = Desired harvest weeks ÷ Sowing interval, rounded up.
Total plants = Total sowings × Plants per sowing batch.
Last sow date is the crop's maturity time counted back from the typical UK first-frost window (~mid-October), so the final batch ripens in time. Approximate seed-to-harvest times used: lettuce 8, radish 4, spinach 6, rocket 4, spring onion 10, beetroot 10, carrot 12, peas 12 weeks. Use the Maturity Time Factor to fine-tune for your variety and site.
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.