Garden calculators
Plan beds, soil, seed starting and indoor growing. 7 free tools, each with its formula and sources.
- Raised Bed Soil CalculatorSoil, compost and mix amounts for one or many beds, in bags or bulk.
- Seed Starting CalculatorWhen to sow indoors, direct sow and transplant, counted from your last frost date.
- Mulch, Compost & Topsoil CalculatorCubic yards, cubic feet, litres and bags for any area and depth.
- Plant Spacing CalculatorHow many plants fit a bed or area, in a square or staggered grid.
- Compost C:N Ratio CalculatorBalance greens and browns for a compost pile that heats up and doesn’t smell.
- Rain Barrel CalculatorHow much rainwater your roof collects and how many barrels or water butts to fill.
- Grow Light DLI CalculatorDaily light integral from PPFD and hours, or the PPFD a plant needs.