Tony Dickerson problem solves
QIs overseeding the answer to my underperforming lawn? Mr M Lambert, Congleton, Cheshire
AOverseeding is a useful way to thicken up a lawn when a seed-sown lawn has germinated sporadically due to drought or low soil temperatures. It’s also handy when you need to repair an area that has suffered from pedestrian traffic. Doing this is best in early autumn or spring, but avoid midwinter. Overseeding is not just a case of scattering seed over the top of an existing lawn. This generally doesn’t work as the seedling roots can’t penetrate the compacted surface typical of lawns. For overseeding to work successfully, you need to disturb the lawn surface, so a good time to do it would be after scarifying in autumn. Alternatively, a simple approach is to insert a garden fork a couple of inches into the ground and then pull it back to break up the surface compaction over the area needing attention, and then sowing over the top. Even for a small area it’s best to measure out the seed, as sowing too thickly or too thinly will both give poor results. When you’re overseeding existing grass, apply 10-15g per sq m (0.4-0.5oz per sq yd). For even coverage, first sow in one direction and then go back over the area at 90 degrees. Lightly rake the area to settle the seed in. In dry weather, water with a gentle sprinkler so seed isn’t washed away.
Birds can be a nuisance as they’ll view the seed as a free snack, so cover it with some netting or horticultural fleece until it germinates.
If an area of lawn has completely failed due to heavy foot traffic, or has been shaded out by encroaching plants from borders, it may be best to replace with fresh turf. The main problem is that it’s difficult to get an exact match, especially if you don’t know what seed was used to create the lawn in the first place. If you want to match your existing lawn, try lifting a section of turf from one end of the existing lawn; it only needs to be about 5cm (2in) thick. Place it face down in a large plastic tray so you can even off the bottom to make it sit uniformly. Lift the damaged turf and use a fork to break up the compacted surface beneath. Gently firm in the new turf and water well.