Tools
Tools & calculators
Simple, no-signup tools that answer one question. More are added with each new guide.
Seed germination rate calculatorWork out what percentage of a seed batch still sprouts.Open tool →Seed starting date calculatorCount back from your last frost date.Open tool →Plant spacing calculatorHow many plants fit in a bed at a given spacing.Open tool →How many seeds to sowTurn a germination rate into a sowing quantity.Open tool →Seed viability lookupHow long different vegetable seeds keep.Open tool →Seed storage life adjusterHow temperature and humidity change seed life.Open tool →Desiccant amount calculatorHow much silica gel to add to a seed jar.Open tool →Cold stratification plannerWhen to start chilling seed that needs cold.Open tool →Seed harvest date calculatorCount forward from flowering to ripe seed.Open tool →Succession sowing plannerTurn one sowing date into a season of dates.Open tool →Cutting rooting time lookupHow long cuttings take to root, by plant.Open tool →Bulb planting calculatorDepth, spacing and bulb count from bulb size.Open tool →Autumn bulb planting date calculatorCount back from first frost to plant bulbs.Open tool →