The "nurse" grasses (such as rye grass), and the semi-permanent types will grow rapidJy. To prevent their damaging the slower-starting permanent grasses, such as the bluegrasses, by their shade or competition for moisture and soil nutrients, begin mowing when the tallest grass is 2 inches. Do not mow shorter than 1 1/2 inches.

Renovating Old Lawns

If you have been struggling in vain with a poor lawn, you might just as well do something drastic with it, such as spade it up and rebuild it. If you do, however, be careful not to build in the same mistakes again. If there are puddles or pools on your lawn for a long time after rain, you may need to lay drain tile or get a good layer of gravel under the topsoil.

If your problem is due to a hard-baked soil and the grass is thin and anemic, spading up or plowing followed by soil preparation and re-seeding, is probably the best procedure. If limited areas (such as paths or low spots or areas under trees) get too packed, they can be loosened and cultivated, or opened up by aerating to a depth of 6 or 8 inches. You can do this with an ordinary spading fork, driven deep and worked back and forth to driven deep and worked back and forth to enlarge the openings. Brush sharp sand or compost into the holes to attain better movement of air and moisture through the soil.

Many poor lawns are due to poor soil conditions and can be improved by a better feeding program. Use 4 pounds of plant food for each 100 square feet of lawn. If the grass is too thin, try plant food along with new seed. If your old lawn is bumpy, level it down, raking top-dressing into the hollows, or peel back the sod, filling in the hollow with good soil and replacing the sod.

A mossy lawn is usually due to poor drainage, not to acidity in the soil, as is widely believed. A mossy lawn may need a change in grading for improved drainage, or raking and liberal fertilization.