How to kill lawn weeds

How to kill lawn weeds

Even if you use a lawn feed, weed and mosskiller early in the season weeds persist and new ones appear in the grass as the year progresses. These can be controlled using a selective lawn weedkiller: one that is specifically formulated for use on lawns. If used according to the instructions it will kill the weeds, but leave the grass unharmed. As with any other weedkiller it is most effective when weeds and grass are growing quickly in the warm days of summer and early autumn.

When to use

Only use a selective lawn weedkiller when the weather is warm and the soil is moist. Do not use during drought conditions when the grass is under stress through lack of water. 

Cut the lawn and wait for about three days before applying the lawn weedkiller: the weeds need to have plenty of leaf growth for the weedkiller to be effective. The more leaf: the more of the chemical that is absorbed by the weeds, ensuring there is sufficient to kill the roots.

Do not cut the grass for a few days, until you see the foliage of the weeds starting to curl and become distorted.

How is it applied?  

Lawn weedkillers can be applied using a watering can or sprayer. The concentrate is diluted in water according to instructions and the applied carefully on a still day, either early in the morning or later in the evening to avoid scorch.

Never use a can or sprayer you have used for other weedkillers unless you have washed it out thoroughly and carefully.

Alternatively you can use a ready-to-use sprayer. This is ideal for small lawn and for spot treatment. If you only have a few weeds, then this is the answer: there is no value in treating the whole lawn if weeds are not widespread. Just target the individuals.

Will it kill all lawn weeds?

Some lawn weeds are easier to kill than others. Those that form flattened rosettes of larger leaves, such as dandelion, daisy and plantain are easy to kill. Those with small, waxy leaves that repel water, especially clover are notoriously tricky.

Vitax Lawn Clear is a specially formulated lawn weedkiller that effectively controls a wide range of lawn weeds, including clover. It is available as concentrate, for treatment of larger areas, also as two sizes of ready-to-use spray. These are perfect to have on hand to tackle lawn weeds as they appear.

How often should it be applied?

One application of Vitax Lawn Clear in ideal conditions should give effective control of existing lawn weeds for a season. Usually spot treatment of individuals is all that is required thereafter. However in severe cases a follow up treatment may be necessary, but not for six to eight weeks.

Do not treat new lawn for at least three months.

Does it affect the grass cuttings?

Yes, do not use the grass cuttings on your compost heap. You could however compost them for nine months and use as a mulch under mature hedges and shrubs, but take care if using near delicate herbaceous perennials and more fragile subjects. Do not use compost containing treated clippings on your vegetable plot or flower garden.

Andy McIndoe for Vitax