Lawn mowing mistake Brits must avoid in August - or risk moss, weeds and grass 'stress'

With warmer days and sunshine expected for the first week of August, many green-thumbed Britons will be heading out into the garden. However, while experts recommend mowing your lawn in August, there is a crucial mistake to avoid.

The Royal Horticultural Society recommends leaving your grass to grow throughout May, June and July to benefit the environment.

"While you can re-start mowing in June, it’s even better to leave the grass uncut until August to preserve the newly created habitat and encourage a greater diversity of plants," explained the RHS.

However, gardeners are urged not to cut their lawns too short. Experts from lawn care brand Greensleeves explained: "If your lawn is mown too short during the growing season, it can be placed under stress and leave it thin and weak.

"This allows moss and other weeds to have a great opportunity to invade any weak or bare areas on your lawn.

"If your lawn has any sparse areas over winter, then it is very likely that moss is going to invade this area and become an issue."

Excessively close mowing can weaken the grass and encourage shallow rooting. In turn, this can make your lawn more susceptible to drought damage, weeds and moss. Short lawns also require more maintenance including frequent feeding.

"To retain a healthy, green appearance your lawn should not be mowed less than 25mm in height," said Greensleeves. "During warm, dry periods you should increase the height of the cut to 40-50mm to retain moisture and a green appearance."

As a general rule, the RHS recommends gardeners aim to keep the grass at the following heights:

• 13–25mm in summer and up to 40mm in spring and autumn for ordinary domestic lawns
• 6–13mm for fine lawns

With new lawns, wait until the grass is at least 5cm tall before mowing with the blades on the highest setting.