Composting is a term that is understood by many people theoretically, but in practice can be quite difficult to achieve the expected results. The post below will introduce this topic in more in detail and give you some ideas to aid you in producing real, good quality compost.
Why is it good to compost?
Composting is the simplest way to create a “nutrition-bomb” for our garden, which can improve the general condition of our soil. This is because our plants are supplied with macro- and microelements from a known, reliable source. Beside these benefits, we can also reuse and recycle our garden and kitchen waste which would otherwise end up in our waste bins, bonfires, or local green waste facilities. Our soil needs TLC just as much as our plants: either it is too clayey and retains too much water or too sandy and water runs straight through it, retaining very little nutrients. But, by adding compost to poorer types of soil, we can improve the structure and water retaining ability of the soil, thus eventually over the years our poorer quality soil can be turned into a crumbling, rich growing media.
Because our plants through the vegetation period are constantly depleting the nutrient resources as they grow, flower and produce fruits, we regularly need to provide added nutrients to our soil. The mature, dark brown (often black) colour, almost soil-like compost contains a wide spectrum of nutrients, which is perfect to use in our garden.
How and where should I use the compost?
We can never have enough compost as it is so versatile to use in the garden. We can use it for soil preparation when we want to lay new turf, create a new flower bed, reseed an area, cultivate it into the soil; or we can apply it in planting holes for plants with high nutrient demand such as annuals, vegetables etc. Compost which is not perfectly ready for planting, can also be used for mulching around trees (covering tree pits) to suppress weeds, retain moisture or even sprinkled onto other pots and tubs.
In autumn, once we harvested all the vegetables and tidied the beds up, we should dig or hoe the ground to a 5-8cm depth, and then we should spread the compost in a good 2–3-inch layer on the top of the ground. During the winter months this layer of compost will slowly get into the deeper layers of the soil. In spring, once the frost is firmly gone, it is worth adding another 2-inch layer of compost to clay the soil.
Herbaceous borders and rose gardens
In autumn, when we cut all the herbaceous plants back and tidy the beds up, we should add a 3-inch layer of compost to the herbaceous border, but do not cultivate it into the ground, just leave it on the surface over the winter. In spring we should repeat this again, but this time gently fork or dig the compost into the soil. We can do the same thing with areas which are planted up with bulbs.
Trees and shrubs
Spread the compost around the stem of mature trees and shrubs in about 30-40cm radius. For younger plants, we should spread it right up to the perimeter of the crown to provide the very crucial, initial nutrient supply for our young trees and shrubs. If we do the composting in autumn, it is not necessary to cultivate it into the soil, but in spring it is highly recommended.
If you have mature, soil-like compost, you can apply that on your lawn too, by spreading a thin layer right after lawn aeration so that rain and irrigation can wash it deeper into the ground.
What can I compost?
For successful composting we need organic matter high in carbon (called “brown materials”), organic matter high in Nitrogen (called “green materials”), oxygen and water. Composting is a biological breakdown process – however if there is a lack of oxygen it can quickly transform into rotting, and the final product would not be dark brown or soil like but rather a smelly unusable mess. Do not compost oily, fatty materials, food leftovers (unless green materials) and faeces from carnivorous animals. The following spreadsheet gives you some ideas about different common materials and the colour coded category they belong to:
|Brown materials||Green materials||Do not compost these!|
|vegetable stems||egg shells||materials of animal origin|
|corn-cob||fruits||oily, fatty materials|
|dry leaves||grass cuttings||food leftovers|
|wood chips or shaving||green leaves||invasive plants|
|pine needle||kitchen green waste||weeds with seed heads|
Is there a perfect recipe for composting?
There is no perfect recipe for composting, but there is well proven ratio: 3:1, which makes our life lot easier. This means we should mix 1 ratio of green materials to 3 ratio of brown materials. This ratio is quite important, because if use too much brown materials it will take quite long for the organic material to break down, but if we have to much green materials the organic material will start to rot instead of breaking down, and this biological process would not attract to macro- and microorganisms living in the soil to turn our organic materials into compost. On compost heaps or in composters, when we add a new layer of organic matter to it, make sure to spread a layer of soil on it too, and if we think it is too dry then add a bit of water to it. The composting material should always be like a squeezed sponge – gently moist, but not overly wet. When the biological breakdown process starts, it creates heat, so do not be surprised if your compost pile feels warm – this is absolutely natural and should be expected.
How to choose a composter and where should I place it?
There are so many ways and methods for composting, the simplest is a compost heap or pit dug in the ground where we collect the green waste. There is also a wide range of constructed composters on the market. Some more aesthetically pleasing and others more practical, but sometimes not so cost affective – but you can always find the one that suits your requirements the best. Whenever you want to allocate an area for your new composting facility, make sure it is a well-drained (not waterlogged) and semi-shady (so to not dry out quickly) area. This area should have comfortable access to be able to put your new materials on easily. When you want to decide about the size of your composting area, always consider the size of your garden and the quantity and form of materials you want to compost. Practically, the best composter is the 3-section composter which allows you to maintain/rotate and have your own compost all year round.
So far, we learnt the background of composting and now let’s see the pros and cons of different composters, which would help us decide on one and also find the best location for it in our garden.
- Wire mash
- Pros: cheap; easy to maintain
- Cons: dry out quickly
- Plastic composter (“machines”)
- Pros: Easy to handle; can take up only a small area
- Cons: Easily gets bin-burnt
- Built hollow concrete block
- Pros: can be bult in larger scale; does not require much maintenance; long life
- Cons: quite artificial; high building cost
- Timber composter
- Pros: can be bult in larger scale; does not require much maintenance; natural
- Cons: can be high building cost (depending on materials used); needs treating and over the years can deform
The “regime” of composting can seem a bit complicated at the beginning, but once we get into the routine, it helps us reduce our green waste, reduce the cost we would spend on buying compost while also providing us with reliable source of plant food, and at the end of the chain… happy, thriving plants. So, we try to encourage everybody who has the option to start composting, begin saving money, and grow healthier plants.