Overseeding

Germination typically starts somewhere between seven and twenty-one days, depending on the seed type, soil temperature and the weather. Ryegrass in the blend is usually first, often in five to ten days; fescue tends to follow in one to two weeks; bluegrass can take three weeks or more. Expect the lawn to look meaningfully different at three to four weeks, and to keep filling in through the following spring. It is a gradual change rather than a transformation you see the next weekend — which is also why we do not publish immediate before-and-after photographs of it.

This is the part worth being straight about, because it usually determines the result more than anything we do. New seed needs the top inch of soil kept consistently moist — short, light waterings rather than one long soak, typically once or twice a day in warm weather, through the first two to three weeks. How often depends on the weather: a cool, damp fortnight needs far less than a warm, dry one. Once the seedlings are up, water less often but more deeply. You will get written instructions before we leave. Seed that dries out for a day or two in warm weather often does not recover, and that is the most common reason overseeding disappoints.

You can, and on a lawn that is only mildly thin with little thatch it works reasonably. But germination rates are markedly better when seed falls into open aeration holes instead of resting on the surface. If you are paying for seed, it is worth making sure most of it actually grows.

A starter fertilizer does help new seedlings, and we can discuss it at the estimate. We are deliberately careful about what we claim here — product application carries its own rules in Connecticut, and we would rather confirm what we are permitted to apply than promise it on a website.

A premium cool-season blend suited to Connecticut lawns — bluegrass, fescue and ryegrass. The exact mix depends on how much sun the lawn gets, which is something we look at during the estimate. You will be told what is going down and roughly how much of it before we start.

Leave the new grass until it is roughly three to four inches tall, which is usually three to four weeks. Then mow high, with a sharp blade, and take no more than a third of the height off in one pass. Mowing too early or too short tends to pull young seedlings out by the roots, and a dull blade tears them rather than cutting. If the established parts of the lawn need cutting before then, raise the deck and avoid turning on the seeded areas.

A steady soaking rain is the best thing that can happen — it saves you the watering. A downpour on a slope is a different matter: seed can wash down into the low ground and leave the high ground bare. If that happens, call us and we will look at what moved and work out whether the thin areas want a second pass. On lawns with real slope we would rather talk about it at the estimate than pretend the weather is not a variable.

Keep heavy traffic off the seeded areas for two to three weeks, and dogs off them in particular. Light walking is survivable; a football game is not. If parts of the lawn cannot realistically be kept clear, tell us at the estimate and we will talk about whether to seed them at all.

Call us. If you have followed the watering instructions and it still has not come in, we will look at it with you and work out what happened — weather, shade, thatch, and soil temperature all play a part. What we will not do is promise a result in advance that depends on three weeks of watering we are not there to do.