With a pandemic still reminding us that we humans are only one species of the many on the planet, it seems a good time to talk about a group of other species which have a massive impact on our lives. Their impact is a mixed blessing in that some of the group such as the disease-causing viruses, bacteria or fungi can sicken and kill us, but others boost our health directly (if we look after them), such as our gut flora and the soil microorganisms. ‘Microorganism’ is a handy term meaning ‘tiny living thing’ that we can’t see without a microscope and includes viruses, bacteria and fungi.

‘You are what you eat’ is a well-known phrase. It appears that if we eat the healthy foods that sustain our inner (gut) microorganisms, they in turn help both our physical and mental health in many ways. Likewise, the soil is full of millions of fungi and bacteria which work to break down soil chemicals to a form that the plants can absorb, so they grow healthily. One of the best ways we can help this process is by providing organic matter for the microorganisms to work on. The best of these is well made garden compost (not the same as seed compost from a bag). Other sources include well-rotted manure, mushroom compost, leaf mould, and other organic materials used to mulch plants. But good compost is king, as it is a well-balanced food.

A good compost should have a pleasant smell, and when it is ready the ingredients that have gone into making it should have broken down pretty thoroughly. Ideally it shouldn’t be soggy, you are aiming for a mix of air, plant materials, and moisture. To make a compost bin, you might get ahold of wooden pallets or similar, like a double box that sits on the soil and gives you a place to contain your garden ‘waste’. Your aim is to add different materials so you don’t have thick layers of any one thing. While you are adding to the pile give it a bit of a stir to mix it, especially if you have a lot of any one thing such as lawn mowings. In dry weather add water if there is any very dry material in the heap. You can put in food waste but don’t include any meat or bones as this may attract vermin. Also leave out any very woody prunings (green ones are ok)—prunings can go into a separate heap in a dark damp place which is good for beetles and other wildlife, including fungi that will break the wood down. A layer or two of farmyard manure will help activate it if you can get it. When your first bin is full, turn it into the other bin, in order to mix everything up again and get air in. Hopefully you will see some worms getting to work. It should then start to heat up and if all is going well it will steam. This heat is the result of the bacteria and fungi breaking down the green matter. If it is cooking nicely and the weather is cold and wet, you might want to put a cover over to keep out the rain and keep in the heat. The results after some months will be a brown crumbly material which can be spread on the garden at any time of year. It may take longer in cold weather.

Fallen leaves are best made into a separate product called leaf mould. You can make a bin for them though some people find putting their leaves into a black plastic bag, tying it at the top and leaving it for a year or even two. Use it the same way. It has fewer nutrients but perhaps it looks nicer, and it adds organic matter. Once spread on the soil, the worms will pull it down under.

You can buy ready-made compost in bulk from companies that make it from the green curbside collection, or from a mushroom farm. The latter may have some pesticide residue, so it is best to ask about this. There are ready made compost-makers, I have no experience of them, but they have fan clubs. A wormery is a form of compost-maker, and the worms are provided with the kit.
You can buy farmyard manure (FYM) in bags or from stables or some farmers. Again it would be worth asking the supplier if they use pesticides on the straw as a few years back a so-called harmless pesticide (weed or pest killer) stayed in the manure for many months and numerous growers’ tomato crops were seriously affected. Tests done to declare chemicals safe can’t cover everything and the side effects may cause great environmental damage. One such group called the ‘neonics’, widely used by farmers (it is effective at killing weeds) is linked with killing bees. DDT was effective at killing certain pests, but it did such a lot of damage before it was banned. We need to use the precautionary principle far more widely in such matters and not wait til disaster strikes, and the lesson here is that just because a product is on the shelf you can’t assume it is totally safe. Always follow directions for use. And to keep a healthy population of microorganisms, don’t use fungicides (which kill fungi).

Worms, bacteria and fungi in the compost and in the soil work to change the nature of the raw materials into something the plants can digest—a total chemical change and a valuable source of nutrients. So composting is very beneficial and re-uses and re-fashions what would otherwise be waste to great effect. Think cake and the raw materials that go into that. Who wants to eat a cup of flour? But a good cake, now, is a thing of wonder!