Weeds are plants that are growing where they’re not wanted. Weeds can take any form and can vary depending on where they grow. Weeds typically produce large numbers of seeds, assisting their spread. They are often excellent at surviving and reproducing in disturbed environments and are commonly the first species to colonise and dominate in these conditions.
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How to beat weeds

• Prevent weeds from taking hold – Keep lawns in good condition. Remove seed heads from weeds. Take care when bringing soil or equipment into the garden.
• Dig them out – hand control of weeds in the early stages is the best method of all. Young weeds are easy to remove and they won’t have had the chance to form seeds that can spread to other parts of the garden.
• Mulching – a layer of mulch will smother weeds and prevent their germination in the soil.
• Herbicides – these are chemicals that kill weeds.

Guide to herbicides

Selective herbicides remove some plant types and leave others unaffected. They are mostly used to remove weeds from lawns.

Examples are:

• Bindii and clover controls. These weeds are also termed ‘broadleafed’ weedkillers.
• Weed’n’Feed products. These remove weeds from the lawn while, at the same time, fertilising the lawn.
• Winter grass killers. These products remove winter grass (a cool season grass) from certain types of lawns.
• Moss and algae killers. Are used to remove moss, algae and lichens from lawns and hard surfaces.

Non-selective herbicides (also called total herbicides) kill every plant they contact.

Examples are:

• Glyphosate – moves through the plant to the roots. Usually takes 2-3 weeks to take effect. Soil is unaffected by glyphosate and can be planted as soon as plants have died.
• Woody Weeders – very effective control for unwanted trees and shrubs (check local regulations before removing trees).
• Once-A-Year Path Weeders – control existing weeds and leave a weed-killing residue in the soil (that lasts for up to 12 months).

Tips for applying herbicides

• Read and follow label instructions carefully.
• When applying to large areas (such as lawns) carefully measure the area to be covered.
• Weedkillers work most effectively when the plant is actively growing (usually spring, summer, autumn).
• Keep glyphosate mixes free of soil or dirt.

Tips for mulching

• Make sure the soil is moist before applying mulch.
• Don’t allow mulch directly contact plant material.