Slender Speedwell (Veronica filiformis)

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General Information: Slender Speedwell is a perennial weed and is becoming more of a problem on lawns in throughout the UK. They spread by both underground and over ground runners. Slender Speedwell used be controlled by a chemical called 'Ioxynil', but this chemical is no longer available and control with the current chemicals is proving quite difficult. Slender Speedwell is more of a problem in closely mown turf than Germander Speedwell.

Leaf: The small leaves are initially kidney shaped but as they mature they become more rounded and have toothed edges.

Flower: The flowers can be seen between March and June. Each flower has 4 small blue / purple petals, the lower petal is slightly smaller than the other 3.

Preferred Habitat: Slender Speedwell can survive in all soil types, particularly moist, nutrient rich soils and can tolerate low mowing

Control: Hand weeding may be possible if there are a few plants in the lawn. It is important to remove clippings whilst mowing the lawn, failure to do so helps this weed to spread. Raking and light scarification may prove beneficial in reducing numbers, once again remove any debris to prevent Slender Speedwell from spreading.

However if the infestation is more widespread a chemical weed killer will be needed for treatment. As we mentioned earlier speedwell is a difficult weed to control. Using a selective herbicide containing fluroxypyr, clopyralid & MCPA will yield the best results. Alternatively a product containing mecoprop-p and dicamba can be used, a repeat application 6 weeks later will be necessary.

Recommended selective weed killers for Germander Speedwell.

Verdone Extra (fluroxypyr, clopyralid & MCPA).
Westland Resolva lawn weed killer (MCPA, mecoprop-p & dicamba).

Applying chemicals can be dangerous if not applied correctly therefore it is very important that you follow the manufacturers application and health & safety recommendations at all times.

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