Sheet a.k.a. Lasagna Composting
Sheet composting is trouble-free and useful if you have plenty of space available.
Sheet composting is an alternative to building a pile, if you do not like the idea of having an untidy heap of decomposing material in your garden. You carry out sheet composting (related to the lasagne method) by spreading your materials in thin layers, directly on to the garden bed. You can use the usual ingredients such as grass clippings, leaves, garden trimmings, kitchen scraps, paper, etc. Be sure to chop or shred it finely and work each layer gently into the soil. Again, it is a slow process, but it takes little effort and as long as you are not in a hurry you can just relax and let nature do its thing. As time passes you can add further layers of material, constantly building up your bed and improving the soil in the best possible way. You may find you do not need a dedicated compost pile if you favour this method, even if you do have the space.
This is a very effective way of getting rid of garden waste such as grass clippings, autumn leaves and garden trimmings (alternatively, if you have a good supply of leaves, you may like to try making them into mulch.) Indeed, you may be able to do a deal with your neighbours – you remove their waste, helping them out and you get the benefits of good compost in return. Because sheet composting is suitable for so many different unwanted materials, you may consider leaving trimmings where they fall, covering them with leaves then working the results into the soil in the following spring. You may even re-cycle kitchen waste in this way, covering it with a layer of grass clippings, or some other mulch. Breaking up this waste by trampling it will help to start decomposition faster. However, you may find that sheet composting is not optimal for the disposal of foodstuffs, as unless you are careful to bury it well, you may find animal friends visiting on a regular basis.
Remember that sheet composting is not a speedy method, as your compost will not attain any sort of heat. In winter, if the ground freezes, decomposition will cease and will not start again until the spring arrives. Also, make sure that in dry conditions, you keep your materials damp.
Creating new garden beds using the Sheet Composting method.
This is also an excellent way of creating new flower or vegetable beds without enormous effort, particularly if you are working on difficult ground. Neglected clay comes to mind here. Anything that can help to make solid clay more friable, lessening the huge chore of digging it over must be good news!
To do this, firstly mark off your garden area and trim all the plants, weeds and all, to ground level. Soak enough newspapers in water to hold them in place and use them to cover the area. About 10-12 pages would be a suitable thickness. Then, cover this paper with several inches of mulch – leaves, grass-clippings and some topsoil, if available. Keep adding extra layers as time progresses and depending on temperatures. In 6 to 12 months, all the previous growth from the roots up will be gone and you will be left with a bed of potentially fabulously rich organic soil just waiting to be planted out. Remember, though, that you only get out what you put in. If you do not use a wide variety of materials to make your compost, the result will be less than fabulous, with poor nutritional qualities.
Problems that may arise with Sheet Composting.
- Experts advise that Sheet Composting should be carried out in autumn, in order to ensure that the ingredients are well rotted before planting takes place in the following spring. The time it takes for decomposition to occur, obviously will depend on the temperatures where you live and in any event, you may be happy to wait for an extended period before you want to plant. However, it is important that you do not hurry as problems can occur if you plant before decomposition is complete, and the carbon-nitrogen ratio in your soil is not correctly balanced. If you have too much brown waste in your compost, the nitrogen will be used to counteract the excess carbon rather than being available for your plants. On the other hand, if you have too much green waste, you may end up with an excess of the wrong kind of nitrogen being released too quickly. Either will result in root damage and poor growing conditions
- If you are working with a heavy soil, such as clay and you decide to use Sheet Composting to make a new bed, you should be careful that the paper you use as your first layer does not strangle the clay and turn it into a solid, unworkable, even anaerobic, surface. This can happen very easily and if it does, you will never get worms and other vital, small creatures to take up residence. They will stick to the compost layer on the top as it is easy living! Use paper that will decompose relatively quickly, (newsprint rather than heavy cardboard) allowing you access to the surface and then, once decomposition has started, use a small rotary hoe or similar tool to mix the decomposing materials into the clay itself. Do this each time you add a layer, so that the materials become well incorporated into the soil. Eventually, the roots of your plants will do a lot of this work for you, breaking up the clay as they grow allowing the finished compost to be carried down by worms and other visitors.
Many people with large gardens choose to compost using this method when they want to prepare new beds. It is very successful and works well if you are a fan of the ‘no-dig’ garden movement. Just collect up those materials and start layering!