How to control weeds

‘One year's seed is seven year's weed’, or so the saying goes, so the most important thing an organic gardener (and non-organic gardener for that matter) can do is prevent weeds from flowering and setting seed. A horrifying example of this is chickweed, where one plant can produce 15,000 seeds a year. The best thing to do is deny them the opportunity to get a foothold in your garden in the first place. There are several techniques you can employ to do this.

Preventing. Mulching is one of the best ways to stop weeds. A thick layer of home-made, well-rotted compost or specially bought loose organic mulch such as bark chips, stops weeds by providing a barrier through which light cannot pass. Put down the mulch while the soil is moist and before the first weeds begin to emerge in spring. If the weeds have already sprouted, they have more chance of pushing up through the mulch. If the soil is already planted with trees and shrubs use low-growing, mat-forming plants, such as vinca (periwinkle) and pulmonaria (lungwort), to cover the ground. Also, use neat edging plants, such as pachysandra, to provide a permanent cover around beds and borders. I’m a firm believer in mulching – not only does it keep down weeds by its physical presence, but it also keeps plant roots moist and encourages them to grow better and do their own bit to triumph over weeds.

Controlling weeds. Hoeing is the best way to control annual weeds and should be carried out regularly on un-mulched ground to prevent them flowering and setting seeds. Hoe when the weather is dry and warm so that the weeds die and any weed seeds brought to the surface don’t germinate. Digging is the best way of removing perennial weeds on vacant ground. However, they can be suppressed using a layer of thick black plastic or old hessian-backed carpet under a decorative mulch to provide a very dense mat they cannot push through. It may take several years to kill them off completely.