Raised Garden Bed Soil Calculator

This calculator works out how much soil or garden mix you need to fill a raised garden bed in New Zealand, giving the answer in litres, cubic metres and bags so you can order whichever way suits. Filling a new raised bed always takes more than it looks, because depth multiplies quickly with the footprint, and buying a couple of bags only to find the bed is half empty is a common frustration. The volume is simply the bed length times the width times the depth, which in metres gives cubic metres, and since bagged soil and compost are sold in litres, multiplying by a thousand and dividing by the bag size tells you how many bags to grab. You enter the internal length, width and depth of the bed, and the bag size you would buy, and the calculator returns the volume in cubic metres and litres and the number of bags. A blend of garden mix or topsoil with compost suits most vegetable and flower beds, and for deep beds you can put coarser material in the bottom to save mix and help drainage. Beds settle over the first few weeks, so it is fine to fill generously at the start and top up later. For larger beds bulk garden mix is usually cheaper per litre than bags. An estimate to plan your order.

Beds settle, so fill generously and top up later. Bulk garden mix is usually cheaper per litre for larger beds. An estimate for planning only.