Instructions

Weeds can ruin the look of your garden and too much weeding can ruin your weekend. In this guide we will cover some of the most effective methods for dealing with them.

A weed is any plant growing where it’s not wanted. They are often invasive and difficult to control and will compete with the plants you want for light, moisture and nutrients. They also attract insects, reduce air flow around plants and act as hosts of disease.

The key to effective weed control is to get rid of them when they are small. It may be that combinations of methods are needed to control them.

Manually

Hoeing or pulling by hand is effective when the weeds are small. This will also prevent them from producing seeds and beginning the cycle all over again.

Hoeing is particularly effective in the vegetable garden, rose beds or flower beds. Cultivating around plants tends to bring other weed seed to the surface so this method will need to be repeated frequently.

Chemically

The use of weed killers is an effective method of killing. You can apply weed killers to large areas and this is especially useful when you have tougher perennial weeds or weeds with long tap roots. Most weed killers need active green growth to work as it is through the contact with the leaves that it is able to enter the plant’s system and destroy its structure. Weed killers can be purchased as a concentrate or ready-mixed for smaller areas of spot spraying. They come primarily with three actions – selective, non selective and pre-emergent.

Selective will only kill the weeds that it has been blended for – the type of weeds that it kills will be shown on the bottle. These types of herbicides are commonly used on lawns where they will kill broadleaf weeds but not the grass. Non-selective herbicides will damage everything the spray touches, even desirable plants in the garden, so special care must be taken to prevent spray drift. Pre-emergent is often used over large areas of paving or cobblestones. Once applied, it acts as a film, coating the soil, so that weeds can’t grow through this barrier. These weed killers can last from 9-12 months.

Mulching

Mulch acts as a protective cover over soil. It supresses weed growth and retains soil moisture to keep roots cool and moist over the hot summer months. By mulching, you prevent weeds from establishing themselves. Weed seeds will germinate beneath mulch, but will be unable to reach sunlight to grow. Organic mulch can be in the form of peat, compost, shredded newspaper, sawdust, pea or barley straw, seaweed, wood chips, bark or lawn clippings - basically any organic material that will break down into the soil.

Apply the mulch in a layer at least 50mm thick to effectively eliminate weeds. Organic mulch has the added advantage of improving soil structure as it breaks down into the soil. Apply organic mulch to the soil in spring and again in autumn. Weed mat is an inorganic mulch that still allows air and moisture in to the soil while excluding the light. Weed mat is best applied to the areas once it is free of weeds. It can be covered with bark, pebbles or crushed shell.