Let's start with the basics. According to a well renowned (quickly googled) online dictionary, compost is defined as "A mixture of decaying organic matter, as from leaves and manure, used to improve soil structure and provide nutrients."
That pretty much covers it. You put organic matter that will decompose in a heap, and after some time a material is produced that you can use on the garden that will improve growing conditions.
This article explains in some depth the reasons why and how a compost heap works, from bugs and bacteria to temperature, what you put on it, and how damp it is. I'll go through a lot of that in a lot less depth below.
So, why compost? Well the two main reasons I compost are to feel a wonderful sense of smugness at not throwing huge amounts of kitchen waste to landfill, and to create a material that will improve the quality of my soil, and therefore the quality of my plants.
Adding compost to the soil will improve the nutrients such as nitrogen, phosphorus, and magnesium. It's open and crumbly nature will, when dug in help to improve the drainage in soil, and oxygen levels. In a selfish respect, digging compost in to the soil makes further digging a lot easier as, especially for clay soils the heavy material is mixed up with that light organic material making it a much better substance for you to work with. If you add compost to sandy soil on the other hand it makes it heavier and better at retaining the moisture it needs.
Basically compost makes everything better. There is no down side!
On to the 'How'. There's the 'what to compost?' question.
There are two generally accepted methods of composting. Hot and Cold. Look here for a quick break down. The hot method is more work but works much faster (and kills weed seeds) the cold method requires little work but takes much longer (also doesn't get hot enough to kill off those seeds, so try not to add too many dandelion heads.) Of course you can mix the two, and start of off 'cold' then turn the mixture often to 'heat' it up (this actually just aids getting oxygen to the mix helping those aerobic bacteria)
Lastly in this 'how' bit I shall send you to google for a comprehensive list of compost bins. Google Compost Bin Search. This I should imagine will cover every style, size and shape of bin out there, from buying ready made to making your own.
My local council provides (and delivers) those slightly conical plastic bins with the hatch at the base at a low cost. I'd advise you look at your local council's website to find if they do a similar scheme.
My plan for myself (when I have a garden big enough to house one) is to build my own wooden (from reclaimed pallets or similar) a three stage compost bin.
This video from Growing Wisdom explains the three bin system. I think this is the system used by Monty Don on Gardeners' World too. It sort of means that you are compromising between cold and hot composting. You put a little more effort than in to cold composting, and you get your compost a lot faster, but you can also keep adding matter to the bins in a continuous cycle.
Who?Um...well, everyone with a garden? (Yes. Everyone...see below)
Where?Anywhere that there is a garden that requires some compost. Including all of you with only a balcony or a courtyard. (yeeah, I heard all you balcony owners starting to whine...)
- At this point, when things thaw from the winter months, the materials that were added to your composter in the winter will start to break down. You can speed this up by keeping your compost well aerated – this will warm up the pile and help decomposition along.
- Finished compost at the bottom of the composter can now be used in your garden. Spring is the best time to add compost to your garden! Mix it in directly with the soil you currently have in your garden, or you can pass your compost through a sieve before placing it on top of your soil.
- Prune your plants and remove any dead plants/leaves from the garden that may not have been removed before the winter began. These products can be added to your composter.
- Summer is the best season for composting. The weather is warm and helps the materials to compost fastest.
- Make sure that you have the right ratio of green to brown material in your composter, and to insure that it decomposes fastest make sure everything is chopped into small pieces.
- In order to keep your composter running smoothly, make sure that there is enough moisture in it.
- Continue using finished compost in your lawn and garden to help your plants gain the nutrients they need to grow healthy.
- Keep up with the composting throughout the fall to guarantee that you’ll have fresh compost in the spring when you need it. Keep in mind that you don’t want to overwhelm your composter with only one type of material (leaves, for example) – you may want to save some of this to layer with the kitchen scraps you add to your composter throughout the winter.
- In order to help keep your composter warm, you can use a cover over it.
- Mix your compost every couple of weeks in order to keep it aerated.
- Finished compost should be spread out over your garden to put the nutrients back into the soil to get ready for next spring.
- Keep up with your composter, even if it only includes making a trek out to it once a week or so with a bucket of kitchen scraps. Everything you add to your composter during the winter will actually break down quicker than you would have expected, due to the way the weather freezes and then thaws your materials.
- Do not mix or aerate your composter at this time of year, as this will cause heat to escape from your composter. If you are worried about heat retention, you can always insulate your composter with straw, hay or leaves around the sides and top of the composter.
So. To summarise: Put decomposable matter on heap of choice, getting mix of brown and green right, mix or turn as often as you want, when its brown, crumbly and smells nice, spread on and mix in to garden. There you go, instantly improve your garden!