Sod care and watering in the first three weeks

The difficulty with new sod is that it arrives looking like a finished lawn. Seed obviously needs looking after. Sod looks like the job is done, and that is why it gets forgotten. For the first few weeks it is a thin mat of grass sitting on soil it has not connected to yet, and it has almost no ability to find water on its own.

Water it heavily on day one

The first watering is the most important one, and it needs to be far more than a surface soak. Water until the soil underneath the sod is wet, not just the sod itself. Lift a corner and check. If the ground under it is dry while the grass is wet, keep going.

That soil to sod contact is where roots have to cross. Wet turf on dry ground is the single most common way a new lawn fails, and it fails from underneath while the top still looks healthy.

Then keep it damp, then gradually back off

For the first week or so, the soil under the sod should not be allowed to dry out. That generally means watering every day, and more than once a day in hot or windy conditions. Sod dries fastest at the seams and along the edges of the area, so check there rather than in the middle.

In the second and third weeks, start reducing frequency and increasing the amount each time. This is deliberate. Roots follow moisture downward, and gradually making the surface drier is what drives them down into the soil instead of leaving them sitting in the sod mat.

By about a month in, a healthy new lawn should be moving toward the deep and infrequent watering pattern any established lawn wants here.

How to tell whether it has rooted

Take hold of a corner of a piece and pull gently upward. Early on it will lift freely. Once roots have gone into the soil you will feel real resistance, and that is your signal that the lawn has knitted in. Test in a few places, because edges and shaded areas root at different rates.

Until you feel that resistance, keep traffic off it entirely. Walking on sod that has not rooted shifts pieces, opens seams and breaks the contact you are trying to establish.

The first cut, and mowing after that

Wait for the tug test before mowing. When you do cut, make sure the ground is dry enough that the mower will not rut it, and take only the top off. Cutting new sod short stresses a plant that is already working hard on roots rather than leaves.

Keep the blade sharp, and consider mowing in a different direction each time so the turf is not pushed the same way repeatedly while it is still soft.

Things people worry about that are usually fine

• Visible seams for the first few weeks. They close as the grass grows across them.
• Slight yellowing in the first week, particularly if the sod sat rolled up before laying.
• Some shrinkage at the edges of pieces in hot weather. Extra water usually closes it back up.
• Footprints showing when you walk across it. That is a sign the turf is short of water, and it is a useful early warning.

Things that need attention

Pieces that stay brown while the rest greens up, corners that curl and go crisp, or gaps opening between pieces that keep widening, all point to the soil underneath drying out. That is a watering problem in almost every case, and it is fixable if it is caught quickly.

Standing water sitting on the lawn for hours after watering is the opposite problem and it needs looking at rather than ignoring, because sod sitting in water will rot at the root just as surely as it will dry out.