Compost: let me break it down

Want early tomatoes? Corn with four fat cobs on the stem? No blackspot on your roses? Beans that give crop after crop all summer? Compost can give you all of those: rich soil, larger crops, more deliciousness fewer pests and diseases.

While compost doesn't kill the pests or diseases, it just promotes a stronger, more pest- and disease-resistant plant.

Compost is both extremely easy and incredibly difficult to make. It's like riding a bicycle - you need instruction, encouragement and experience, but once you have these you will find compost making easy.

But you do need to know how to make compost - the 'buy bin, bung and hope' method rarely works. If you get riding a bicycle wrong you'll end up with skinned knees or worse. If you get compost making wrong the rats will have a feast, then make condominiums in your roof space to breed baby rats, and the fruit fly will multiply and turn your peach and apple crop into bruised balls of little wrigglers.

Earwigs, house flies, codlin moth and other pests enjoy 'not really compost at all' heaps too.

The main problem with modern compost making is the expectations.

Compost systems were not designed for leftover pizza, mouldy lasagna, or the carrots you forgot were in the fridge and turned into sludge.

Compost's heyday came in the time when farms and even back gardens had access to plentiful manure from hens, delivery horses, backyard cows as well as a style of gardening that meant compost makers had access to plentiful autumn leaves, winter and summer prunings and cutting back of perennials every fortnight or so.

Compost needs large amounts of green matter as well as coarse plant material like stems and prunings to help aerate if.

No air equals no compost, except for anaerobic compost systems which we won't go into here, as the simple ones stink and the complex ones would take more words than I have here.

Compost also needs a reasonable amount of nitrogen and phosphorus to break down quickly. Sawdust and woodchips will compost, but unless they have added nitrogen they will take several years to do it.

The kind you roll helps aerate the stuff inside and will give you faster compost. It also keeps the compost out of the reach of rats and smaller dogs. The static fiberglass 'just put it on the ground' kind is basically just a neat container to put the rubbish in.

How to do it: Place the bin in a hot, sunny place. Throw in garden waste as it comes to hand but try to layer leaves with larger material, and scatter hen manure, pelleted or home grown, at least twice per bin full. Wait. A full compost bin will evaporate down to a half-full compost bin in a hot week.

You can use it after about eight weeks - pull the bin up, use the material that has composted at the bottom, then fork the rest of the stuff back in the bin.

(Compost is ready when you can't see what it's made of, not counting the Lego and teaspoons that were thrown in by accident.)

This is old-fashioned compost making. It's fast, effective and hot and heavy work.

How to do it: Build two three-sided stalls, like horse stalls but small. Throw in waste and fertliser as above, but fork the stuff from the first bin to the second bin twice a week. The compost will be gloriously aerated and ready in about three weeks, or sometimes sooner.

(This actually isn't compost, but does eventually turn waste back to soil).

How to do it: Dig a hole. Bury waste. Cover each 30cm layer with 60cm of dirt.

I've seen worm farms where paper, cardboard and leftovers were turned into excellent compost plus a liquid that made the geraniums quiver and promise to be Olympic Champions if only they were given more. I've also had more emails than I've wanted to count asking what killed the worms/why did they escape/why has my worm farm turned into what looks and smells like a bioweapon?

Worm farms can be excellent. Beyond that I know nothing.

How to do it: Throw all garden waste under large trees and let the lyrebirds turn it over as they scratch and look for insects and other edibles, aerating it all wonderfully so that even medium-size branches turn into soil in a year.

If your garden is lyrebird deficient then chooks will do the job about 1/50th as well.

However both hens and lyrebirds will also scratch up all the rest of your garden, unless tactfully prevented.

Compost also needs to come with a warning: it is not for the immune compromised, nor pregnant women as it may have spores you can breathe in or that will irritate your skin. It probably won't, but gloves and the right kind of mask are recommended.

And be realistic. Australia's first recorded compost was made from chopped up tussocks, bark and quite possibly human waste too. (Do not add the latter). If your garden doesn't have lots of green waste, and your neighbor doesn't have a full green bin and is happy to give you the contents, don't rely on lettuce leaves and discarded silverbeet stalks alone to provide enough green waste for your compost. Scraps were never a part of compost practice - they used to be valuable hens, dogs, cats, or pig food.

Well-tended compost will give you magic. Badly made compost will give you rats, mice, fruit fly, codlin moth and a mess if the dog gets into it. You have been warned.