How long does compost take to be ready?

In a well-managed bin, compost can be ready in 6-12 months. Hot composting can produce usable compost in as little as 8-12 weeks.

Should I have two compost bins?

Having two bins is ideal: one to fill while the other matures. This gives you a continuous supply of finished compost.

What can I put in a compost bin?

Green materials: fruit and veg peelings, grass clippings, tea bags. Brown materials: cardboard, dry leaves, woody prunings, paper. Avoid meat, dairy, and cooked food.

How long does composting take?

A well-managed hot compost bin produces usable compost in 8-12 weeks. Cold composting takes 6-12 months. Turning regularly and balancing green/brown materials speeds things up.

GardenCalcs

Compost Bin Size Calculator — What Size Compost Bin Do I Need

Work out the ideal compost bin size for your garden and kitchen waste.

Waste Type

Garden Area

Household Size

How We Calculate This

This calculator estimates your weekly organic waste output based on garden size and household members.

Garden waste is estimated at ~0.5 litres per m² per week (averaged over the year). Kitchen waste is roughly 3 litres per person per week.

The recommended bin size accounts for 6 months of accumulation at 70% fill capacity, allowing space for turning and aeration.

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.