The great British scientist Charles Darwin of 'theory of evolution' and 'natural selection' fame spent 3 full years on his famous and revolutionary book 'The Origin of the Species'. However and less well known, before this seminal work, he spent 10 years full-time studying and researching the activity of worms, invertebrates and micro organisms in what he called 'the fermentation of vegetable matter' - or as we call it, composting.
Composting is quite simply nature’s way of recycling dead organic matter.
- Has understandably been described as black gold.
- It returns nutrients, vitality and structure to the soil.
- It is a valuable resource for garden crops & flowers.
- It's entirely natural and produces a valuable product
- It's good for our environment - landfill; collection; transport etc (and we are running out of space)
- It can reduce your Council Tax! (well, reduce the rate of increase) - collecting, transporting and disposing of household and garden waste is very expensive.
- It's free and saves you buying someone else's waste - neatly pre-bagged but expensive.
- It helps break up clay soils.
- It improves water retention (less evaporation).
- It improves drainage.
- It increases worm activity (which is good for every part of the garden except, perhaps, the lawn!)
Composting is easy - and easy to get wrong!
All you need is a little knowledge and the right ingredients. We all have our own ideas of how to compost, some are successful and others are not. If you are happy with your method, then do not change. However, there are some BASIC PRINCIPLES which can help ensure success.
It's all about the right ingredients!
YES PLEASE :-
- Grass clippings
- Dead Plants
- Food scraps (vegetable and fruit)
- Tea/coffee grounds
- Twigs/chopped wood
- Herbivorous pet waste - the small furies - guinea pigs, rabbits etc
- Hair, dust waste, newspaper.
NO THANKS :-
- Weeds gone to seed - they may germinate.
- Dairy products
- Dog/cat waste - unpleasant / risk of toxicara virus
- Thick branches
- Diseased material
- Pernicious weeds - bindweed/cooch or twitch grass/ground elder
Now we know what can easily be composted what do we do?
The materials we can compost can be split into two lists: -
- Food scraps
- Grass clippings 'sappy'/'green' waste
- Rotted manure
- Woody twigs
- Wood chips
- Straw 'dryer'/'brown' waste
- NITROGEN /GREEN = SAPPY/WET
- CARBON / BROWN = WOODY/DRY
To get trouble-free compost it is best to have about
2 parts nitrogen
1 part carbon
They COMPLEMENT each other. Carbon traps the air (physically not chemically).
How to compost
Many gardens in summer have 99% grass clippings (i.e. Nitrogen).
What can be done?
Newspapers/cardboard scrunched up.
Keep adding kitchen waste.
ADDITIVES - Are they necessary?
This is a common question and there are several reputable products. A compost activator is simply a rich source of nitrogen. Don't bother if you have a good mixture of waste. A good heap will build up micro-organisms quickly on its own - this can be helped by mixing the heap.
The cheapest and most highly effective natural additive is, believe it or not, human urine. That said how you get it into the compost bin is up to you!
So, now we've got the ingredients, what do we do?
There are two main ways to make compost at home:
The easy method (the lazy way - my way!)
- Add as you go
- Maintain 2 parts sappy/nitrogen
- 1 part woody/carbon
- Keep adding until the bin is full and well settled. Finished compost is at the bottom. Better still have 2 or more compost bins. When you start composting it's amazing how much you can actually compost. I have a small garden but run 7 composters and a Wormery.
The quicker method
- Build up pile of material all at once (same Carbon / Nitrogen mix)
- Fill the bin all at once
- After 1 week, turn pile
- After 1 more week, turn pile again
- Cover pile with black polyethylene or 2 and composter then start again
- Compost will be ready in 3-4 months.
Why use a composter?
Because it's quick, simple and tidy (nature works to its own timescale).
There are 4 key stages of composting: -
- 55F to 70F bacteria called psychrophiles (sack-ro-files)
- 70F to 90F mesophiles come in to do the REAL work, They eat everything in sight. They can increase the temperature to 100F then die out.
- 90F upwards thermophiles do the really hot work. They last 3-5 days - the heap gets very hot! Too hot to handle! This helps to kill any weeds and seeds etc...
- THIS IS THE TIME TO TURN THE HEAP!
This will pump more air (oxygen) into it and gives a better mix.
When it cools down, there is still much improvement to go.
Worms, woodlice and other invertebrates move in (the worms can eat their own weight each day). All these beneficial creatures help to break the compost down to finish the job.
With all this going on, the heap needs a little protection - a Compost Bin.
Key features to look for:-
1) Size - The bigger the better - but it's better to fill a small bin than to only half fill a larger one.
2) Colour - Dark is the best to absorb & retain heat.
3) Shape - Conical = good drainage and good air circulation.
4) Solid - no air holes - weather. Aeration is critical but comes from having the correct mixture of compostable waste - the Carbon & Nitrogen mix. External vents in a compost bin serve only to aerate the outer layer of waste and in so doing cool and slow down the whole process. So although they may superficially sound like a good idea - so do not be fooled by marketing gimmicks.
5) Doors - Not necessary, not better, not easier to use, but popular - personal preference.
COMPOST - THE END PRODUCT
Don't expect your compost to look exactly like the compost you can buy unless you are prepared to take the final step.
You are producing a truly excellent soil conditioner rich in nutrients to use as a top dressing, mulch or dig into your garden.
If you want it to look just like what you can buy from the Garden Centre - simply dry it out and run it through a garden sieve of griddle - on the other hand why bother - unless your planning to sell it at the local car boot sale!