Lawn repair: when to reseed, patch or re-turf

Why lawns go patchy

Grass thins for a handful of reasons, and it helps to work out which one applies before spending anything. Heavy shade from a fence, shed or tree starves the grass of light, so it gives way to moss. A route that people or pets walk every day compacts the soil until roots cannot breathe. Dog urine scorches round yellow patches with a darker green ring. Clay soils that sit wet through winter rot the roots, and a dry summer on thin topsoil leaves brown areas that never fully recover.

Builders' rubble buried just under the surface is surprisingly common in newer gardens and shows up as strips that always brown first. A garden fork pushed in at a few points soon tells you whether the soil is decent, compacted or hiding something.

Reseeding bare patches

Reseeding suits scattered bare areas and thin grass where the soil itself is sound. The dead grass and moss are raked out, the surface is loosened to a shallow depth, and a little fresh topsoil is worked in to level any dips. Seed is spread evenly at the rate on the box, lightly raked in and pressed down so it sits in contact with the soil.

Seed needs steady moisture and mild temperatures to germinate. It is the cheaper repair, but it is also the slower one: the new grass takes weeks to knit in and the area has to be kept off while it does. Birds are the other enemy, so a light cover of fleece or netting can make a real difference.

Patching with turf

Turf patches give an instant green surface and suit worn edges, dog patches and areas next to paths where seed would struggle. The damaged section is cut out in a neat square or rectangle, the soil underneath is loosened and topped up, and a piece of new turf is cut to fit snugly, set slightly proud and firmed down so it settles level with the surrounding grass.

• Cut the damaged area out with straight edges, not a ragged hole
• Loosen and level the soil so the new roots can get going
• Lay the patch tight to its neighbours with no gaps at the joins
• Firm it down and water it thoroughly straight away
• Keep it watered for the next couple of weeks unless rain does the job

When re-turfing the whole lawn is the better job

There comes a point where patching is throwing good money after bad. If most of the lawn is moss or broadleaf weed, if it has sunk unevenly over old trenches, or if water lies on it for days after rain, the ground needs proper preparation: clearing, cultivating, levelling and sometimes improving the drainage before new turf goes down. Patching on top of those problems only buys a season.

The turfing cost guide explains what goes into a full re-turf and what affects the price. For a small garden, a new lawn is often done alongside other work such as edging or a path, which is covered in the small garden on a budget guide.

Best time of year for lawn repair

Early autumn is usually the best window. The soil is still warm from summer, rain is more reliable and weeds are slowing down, so both seed and turf root quickly. Spring is the second choice, once the ground has warmed up and before the dry spells begin. Turf can be laid for much of the year as long as the ground is not frozen or baked hard, but seed is far fussier about timing.

Midsummer repairs are possible but need regular watering, and anything done in a hard frost or waterlogged ground is likely to struggle.

Looking after repaired areas

Most failed repairs fail in the first month. Keep the new grass watered, keep feet and pets off it, and resist cutting it too soon. When it does get its first cut, set the mower high and take only the tips. Over the following months, deal with whatever caused the damage in the first place: a stepping stone path across a worn route, cutting back an overhanging shrub, or rinsing a dog patch with water soon after it is used.

Lawn repair is one of the garden jobs CRF Services Ltd takes on as part of landscaping for modest gardens around Rochester and Medway, and the landscaping in Maidstone page covers how garden work is planned further out.

Frequently asked questions

Landscaping