Save money by making your own compost mixes!

Well rotted compost can be mixed with other organic materials to make perfect seed sowing and potting compost. To get the compost out of your bin lift it off its heap,if you have a plastic composter as it will keep its shape like a sandcastle, and you should find that the bottom 30-45cm is ready for use. [A hatch at the bottom makes it harder to get all the compost out from the back, so if you have a small or medium sized hatched bin, lift the whole bin up and do not use the hatch.]

You bulk up your compost by mixing in:
Leafmould – the best material, but it can be difficult to make or to have large enough quantities.
Coir -a by-product of the coconut industry, is quite readily available, and is a good bulking agent. It is not suitable for ericaceous plants, but otherwise encourages good root growth.
Sieved garden loam is often a valuable addition to a potting mix.
Composted municipal green waste, often sold as soil conditioner, will provide you with a good bulking agent, and can be used instead of leafmould or coir in the mixes below.
Perlite, coarse sand and composted bark are useful in mixes needing good drainage.

Do not use peat or peat based products: the plants and creatures that depend on the world’s peatlands need it more than we do and there are many excellent alternatives.

Prepare your mix by sieving compost and other matrials in the proportions recommended below. The best and easiest tool for sieving is the Rotasieve, available from Harrod Horticultural. We have found this produces superb results quickly and easily, so have used it at home for many years and in workshops on organic growing. To prevent clogging, make sure the ingredients are dryish, only slightly moist. All you then need to do is turn the handle and see the sieved compost build up, ready for use. It is also simple to mix in other ingredients as you sieve.

Young seedlings need very little feed, but as the plant grows, richer mixes are used.
Seed sowing mixes
You can use various mixes, but the best all-round one is: Loam + leafmould or coir + garden compost 1:1:1
Potting mixes
The best mix for plants ready for pricking out and potting on is: loam + garden compost + coir, municipal compost or leafmould 1:2:1
Other ingredients, like sharp sand or perlite, may need to be added to the above mixes, when a particularly free draining compost is required.