Neil Sperry: Planting grass for a mid-summer lawn makeover

Starting new turf grass in July is somewhat akin to joining a marathon at full speed without a warmup. It can be done, but things are moving at the fastest possible pace, so your margins of error are far less than usual.

Assuming you’ll be planting St. Augustine or Bermuda sod, the grass won’t mind the high temperatures (both are “warm-season” grasses), but it won’t have strong roots initially, which means you’ll have to baby it at the outset.

Let’s back up a bit, though. Why are you planting grass anyway? If you’re dealing with a new lawn or you’re converting from one type of grass to another, keep reading. But, if your goal is to cover bare areas beneath trees, stop right here.

First off, you’ll need to examine why the grass that used to be there isn’t there any longer. Foot traffic is rarely the reason, nor is erosion. And it’s probably not because the tree got all the nutrients and water either.

That leaves you coming back to shade as your answer, so you might want to step over to another part of the nursery. Instead of focusing on new grass, your best choice would be to shop for some shade-tolerant ground covers that can survive in low light that’s too dark for St. Augustine.

For those who are “still reading” and really do want to plant new grass, your first job will be to prepare your planting area properly. You can’t just lay sod down over old grass and expect it to grow well and look good. So, here’s your step-by-step plan of action:

A clean slate

Apply a glyphosate-only (no other active ingredient) spray to kill all existing vegetation. Give it a week to do its work. Check local nurseries and sod yards to compare prices and quality. Let them know how many square feet of ground space you’ll be covering. They’ll help you convert that into the numbers of pieces of sod you’ll want to buy. Allow 15 percent extra for waste and breakage. Some sod always tears and becomes difficult to put in place.

Rototiller time

Once the herbicide has killed the existing vegetation, till to a depth of 3 or 4 inches using a rear-tine rototiller. This will pulverize the soil more finely, making it easier to rake the ground to a final grade that slopes gently away from your house. Use a rigid garden rake turned upside-down to accomplish that smoothing.

Checking the sod

When you go to pick up your sod (or have it delivered), do so early in the day. It will have been dug late afternoon the prior day and transported overnight. You want it as fresh as possible, so mornings work best. Turn several pieces of sod upside-down to see if you find any evidence of nutsedge in the sod.

If the sod cutter has sliced through any pea-sized root structures that are interlocked one to the next, don’t buy that sod.

Smoothing seams

Your biggest challenges in planting sod will be to snug up the corners and to push seams together so the surface will be even. Be careful, as you walk on the newly planted grass, that you’re not leaving deep footprints. As soon as you finish one part of the planting, water it to keep the grass fresh.

Keep laying the pieces in place until you have the entire area covered.

Frequent watering

Water the new grass for five or seven minutes once or twice daily for the first week. You don’t want to keep the soil soggy, but you also don’t want to risk letting the grass get too dry before it can grow new roots. After all, it was dug and transported with much less than 1 inch of topsoil and roots.

It’s not uncommon for new grass to look worse for three or four days before it bounces back to normal and starts growing vigorously.

Mowing and fertilizing

Mow your new grass as soon as it’s tall enough to require it, generally after a week or so. Mow at the recommended height. Allowing the grass to grow taller quickly weakens it. Fertilize your new turf after the second mowing. Apply an all-nitrogen plant food with half or more of its nitrogen in coated or encapsulated slow-release form.

The first feeding should be at half the recommended rate. Fertilize again one month later with the same material at the recommended rate.

Consider rolling

If, after a few weeks of maintaining your new lawn, you feel that it still has uneven spots, rent a lawn roller. Fill it partially with water, and roll the grass smooth. Rolling works best after a thorough watering or soaking rain. Do not, however, make a regular habit of rolling the lawn.

Finally, the other aspect we need to discuss about new sod is when a homeowner wants to make a transition and convert a Bermuda grass to St. Augustine turf. Since St. Augustine is the dominant grass of the two, that changeover is easily made — although you should be willing to wait six to 12 months for the final result.

Simply buy the very same top-quality St. Augustine sod or plugs and insert the checkerboard pieces of it into your existing Bermuda. Use a flat-bladed nursery spade to dig shallow holes 6 or 7 inches on a side. Remove 1 inch of Bermuda and its soil, and replace it with a piece of St. Augustine cut to the same size. Use loose soil to fill the gaps. Space the plugs on 15-inch centers, and you’ll have full coverage either by frost or by early next summer.

This story was originally published July 9, 2015 at 11:39 AM with the headline "Neil Sperry: Planting grass for a mid-summer lawn makeover."