Clearing your new vegetable or fruit plot of any annual or perennial weeds involves hard graft, whichever method you use. The first task is to check your plot to see if there are useful shrubs and trees that you should retain. All too frequently, I have seen lovely good cropping old fruit trees, cut down through ignorance. Ask your neighbours to tell you about what you should retain before the chainsaw massacre takes place! If you are allowed to, burn all woody growth, so that the nutrients are returned to the soil. Once you can see what you are doing, plan your campaign to get rid of all the weeds, particularly the perennial ones. There are three basic methods:-
Dig over the plot with a fork and hand weed. Slow and back-breaking but good for the soul! Annual weeds, such as groundsel, chickweed, can be dug well in, or placed in the Compost Heap to rot down. Perennial weeds, such as ground thistle, bindweed, ground elder, mares tail and buttercups, should be put aside to dry off in the sun and then burn them.
Never, never, never use a rotavater on ground with perennial weeds in it, as each tiny bit of the root will regrow into a new weed. Far better to dig the weeds out by hand, keeping the bits of root as big as possible. Never put the perennial weeds on the compost heap, but burn them or put them into a plastic bag to rot.
Spraying with Chemicals. While it is not an Organic method, it can cut the time required to bring badly neglected ground back into cultivation. Spraying with Glycosate solutions, (Ammonium Sulphamate is unfortunately no longer available), will help to kill the foliage and penetrate the root system to some degree, as these are so-called systemic weed killers. The sprayed weeds should be fully dead after about 6 weeks, allowing you to carry out your digging. Another weed killer is Sodium Chlorate(no longer available in the UK), but this is a total weed killer and will poison the ground for 6 months to a year, depending on the strength of the solution. It will also burn any living matter that comes into contact with the chemical. It might be suitable for use on paths, where you want to deal with a reservoir of obnoxious perennial weeds. However, be aware that it can leach into the surrounding growing areas. All weed killers should only be used in accordance with the manufacturers instructions. You should also use protective gloves and prevent any spray getting onto your skin.
Prolonged exclusion of light. This really means taking the ground out of cultivation for several months during the growing season, by covering with old carpets, weighted down cardboard or weighted heavy duty black plastic, to exclude light for a few months, until most weeds are dead. The longer the better to kill the perennial weeds, as they will be dormant over the Winter, and they only need light during the growing season. Do not use clear polythene as you only grow bigger weeds as shown in the photo!
At the end of clearing your ground you will have piles of weeds, including their roots. Compost heaps are an essential way of recycling the annual weeds and other vegetable rubbish, and returning the nutrients that they contain to the soil. The weeds will have a lot of your best topsoil attached to their roots, and it will be returned to your ground at the end of the composting process. For details of the construction of compost heaps, see Organic gardening.
The perennial weeds like nettles, couch grass, docks, bindweed, ground elder, and marestail, are such toughies that it is essential to keep them separate from the other weeds and give them special treatment to kill them. You can leave them to dry off in the sun, and then burn them. Alternatively, put the weeds into a black bin liner, tie off the top and leave to stew in the sun for several months, or even drown them in a container of water for several months.