What do you do if you don't have the right ingredients to make an organic compost bin?

Textbooks tell you that the ideal organic compost is made from a balance of 25% high-nitrogen foliage like bean or pea residues plus 45% fast-rotting materials - weeds, kitchen scraps, lawn clippings - plus 30% woody matter like shredded newspaper, straw or ancient leaves. A little high-nitrogen manure or urine is also valuable to start the fermentation process, especially in cool weather.

But suppose we don't have these to hand?

1. Crumpled cardboard is a compost bin's best friend

Solution: a mixture of kitchen waste and crumpled cardboard! All by itself, it will produce usable organic compost. Nitrogenous lawn clippings accelerate the process and add nutrients. If you don't have a lawn, perhaps neighbours can save their lawn clippings for you? (Just be sure they haven't sprayed the lawn with pesticides or other chemicals in recent weeks.) But lawn clippings are optional.

2. Not enough kitchen waste?

Suppose you can't muster enough kitchen waste? Even a large family of vegetarians might be hard pressed to fill a bin with their own vegetable trimmings alone. In fact, a well balanced compost bin is never full. So fast will your garbage shrink in warm weather that you'll swear somebody is stealing it.

One answer is to scour local independent greengrocers and farm shops and beg for their throwaways. Say candidly, you're an organic gardener and are setting up a recycling round for compostable waste. Most will be truly grateful if, every week, you relieve them of the chore of disposing of plants that are past their 'sell by' date. (Let it be whispered, many such a fruit or vegetable is still perfectly good to eat.)

Another idea is to leave your own plastic bin at restaurants or bars with a brisk food trade and ask them to fill it with vegetable trimmings. Uplift it every week. Just one outlet like this will give you more kitchen waste than you can use. To thank them, give them a basket of your home-grown organic vegetables now and again.

3. Suppose you want to compost other forms of waste?

There's nothing wrong in putting meat or fish waste in a bin, whatever the textbooks say. It will compost down as well as anything else that has ever lived. But next day, the bin will be scattered all over your garden by cats, large birds and rats. (Is this what they call 'sheet mulching'?) Best stick to vegetable waste, raw or cooked.

Contrary to myth, most leaves are also fine. But steer clear of oak, chestnut, beech, pine (and other conifer) leaves. They compost slowly, make the heap acidic and decompose by fungal rather than bacterial action. A fungal compost that has decomposed in this way is good for trees and shrubs but not ideal for vegetables.

A small amount of even acidic leaves are okay, however, if you mix them with lime or powdered eggshells. Or if you love work, you could shred acidic leaves so they decompose quickly, by dunking them in a barrel and working them around with a strimmer.

4. Suppose you want to save compost for next year?

It's true that the best organic compost is that which comes straight from a cooled heap, at the time when the worms and pillbugs (wood lice) are just moving in. The micro-organisms beneficial to soil health are then at their peak.

That's why professional growers insist on fresh compost each year. But if you have too much compost, don't let it sit in the bin. Transfer it to plastic manure bags or the like, and keep in a dry cool place, and it will still be full enough of nutrients next year.

5. To make organic compost very easily

If you want to make compost very easily, fill a strong big plastic bag - like an empty manure sack - with the layers I suggest above. Tie it loosely at the top, so gases can escape. And leave it in a warm place. Even your bathroom.

The compost process is fairly odourless and will proceed anaerobically (without oxygen). In hot weather, you will have black nutritious 'compost' - as slimy as fresh cow manure - within three months.

A great benefit of 'plastic bag' compost is that you can periodically kick the bag around your courtyard to mix the ingredients. This is very good exercise. When the compost is ready, you need merely toss in a few spades of topsoil, plus a little sand, perlite or leaf mould.

Kick the bag around the garden a bit more to mix its contents. Perforate one side, cut planting holes in the other side, and... you'll have a ready-to-go tomato grow bag!