Give me a compost heap and I am in heaven. I think one of my favourite things about the garden is composting; I get hours of pleasure from it. It is satisfying on so many levels and appeals to the less glamorous side of my character: thriftiness, waste-not-want-not, something for nothing and getting down and dirty. Homemade compost is free and the plants can’t get enough of it. Good, well-rotted compost is a joy to behold. A rich dark brown, sweet smelling crumbly mixture is the end result you are looking for.
The first thing you need to do, if space allows it, is set aside a corner somewhere out of the way. Ideally you need at least 2 heaps (I am so crackers about compost that I have five) – one for fresh material and one that is maturing. The best container for compost is a coral made from either old palettes, slats of wood or chicken wire on posts. I don’t really have the space for this so I have four bins and one heap. Always have bare earth on the ground underneath the heap and keep it warm and covered. This stops it drying out and keeps it toasty which speeds up the rotting process.
Once you have the spot for your heap established you can start the fun bit, which is filling it. There are two things vital for good compost; the first is air – the bacteria which break down the heap need oxygen to multiply, if there is no air the heap stagnates and anaerobic bacterial get to work making a revolting, smelly sludgy mess. The second is moisture, if the heap gets too dry it will not start to cook but too much moisture will also reduce the heap to a putrefied gunk.
The best results come from a good layered mix of dry and moist ingredients of differing textures. So if you have put on a layer of sappy green leaves, plant trimmings, annual weeds or grass the next layer really needs to be a brown one. Brown stuff includes dry organic matter, shredded newspaper (not glossy magazines), shredded cardboard and old compost. If you have enough heaps You can add pretty much all your kitchen waste to them bar cooked meat (attracts rats) and really anything that was once alive, so the contents of old feather pillows, moth eaten jerseys, and of course the contents of your hoover. Over the years we have had hamsters, gerbils and a rabbit called Basil. When I was cleaning these small rodents cages a thought struck me ‘here I have the perfect compost mix’ – a nice bit of urine soaked newspaper, some droppings and a bit of sawdust – perfect I thought. I hadn’t factored in the remains of pet food; lots of seeds, and was greatly puzzled to find a fine crop of barley growing in my front flower bed. Almost ten years later I am still pulling out barley. If you have birds the consequences can be even worse – I have heard of a sweet old lady getting a visit from the police about the luscious cannabis crop growing away in her front garden – a result of hemp seeds from her budgie’s cage (though as the late, great Christopher Lloyd said, Cannabis sativa has such lovely foliage!). If you only have one or two piles you are probably best to stick to old organic material.
The bit I like is the fiddling around with heaps. The more you turn the compost the faster it decomposes as the microbes multiply and get to work faster. While turning you can take out any stems that are too woody and lots of things like missing teaspoons, secateurs, trowels and reading glasses that have inadvertently ended up in the mix. If it is looking too smelly or wet, add some dry materials. Likewise if things are a bit dry, spray the hose over it. When you are turning the heap you should see hundreds of worms, this is a good sign that things are breaking down well. If your heap is full of flies it may be because you have added a lot of old fruit, but don’t worry about it, they are only doing their job, just throw a layer of dry material on top. Ants in the heap are a recurrent pest in my garden, especially when the compost is too dry. Ants can be beneficial to the composting process, they break down vegetable and fruit scraps for smaller organisms in the decomposition process and their tunnels promote aeration but if they are getting out of control spray water into the bin, add plenty of organic material to make it too hot for the ants comfort and give the contents a good turn.
If you have the luxury of a big garden and enough fresh plant and vegetable material to put on your heap you can have a few enormous piles which will heat up to a high temperature strong enough to kill weed seeds and even dandelion tap roots. The more material you put on a heap at once, the hotter it gets and will make perfect compost within 6 months or so. Most of us only have small heaps with material being layered on in dribs and drabs, so you are really best to put the nasties into the bin or onto the bonfire. You can buy compost activators which are supposed to speed up decomposition, but to be honest, left over wine and urine (yes really) are just as good.
When the heap has rotted down and is uniformly brown, crumbly and clean smelling it is ready to be used. If you have puts weeds and flowers with viable seed heads into the compost you will probably get a lot of seedlings growing from it – these can be gently pulled out by hand or destroyed by using a hoe.