Don't wait to begin battle with crabgrass

3/24/2010

Do you remember those low- growing patches of weeds in your lawn last year? They spread out wide and take over the lawn quickly if your turf is stressed out. That is crabgrass, and you can treat your lawn early in the season to stop it from growing.

So, get to your favorite home and garden center and pick up something to fight that crabgrass and feed the turf. Look for a pre-emergent herbicide. This type of chemical won't hurt your grass, but it will stop the crabgrass from sprouting. Usually it is mixed with fertilizer, so you are doing two things at once.

The soil is still a bit cool right now, but seeds from crabgrass start to germinate when the top layer of the soil is between 50 and 55 degrees. The best time to apply it is in late March and all through April. When the crabgrass seed hits soil treated with a pre-emergent herbicide, it stops growing.

Look for name brands like Balan, Pre-M, Pendulum, Team, and Team Pro that contain chemicals such as benefin, pendimethalin, and trifluralin. These all can be applied before the weeds take hold of your rye, fescue, and bluegrass.

Another common pre-emergent is Dimension. Its active ingredient is dithiopyr and it's a good crabgrass stopper. Other products like Betasan contain bensulide and work well on bentgrass lawns. Ronstar G contains oxadiazon, but shouldn't be used if you have bentgrass or fine fescue or are planting a new lawn.

Sometimes crabgrass is our friend. If you can grow only crabgrass in some compacted bare spots, avoid the fertilizer laced with pre-emergent herbicide to let the low weed fill in. Put those areas on your list to improve this year so you have some nice turf growing later this fall.

Give your lawn a nice combing with a rake. Go over the whole lawn to pull up all the lose debris that remains from fall. Pull all the leaves off your flower beds, and any that are stuck in the bushes, and toss them on your compost pile.

If you don't have garden edging, now is a good time to go around the beds with a sharp spade to keep their lines free from encroaching turf. Get a truckload of fresh mulch or compost to spread on your emerging flower beds. A three to four-inch layer of mulch will smother any weeds that might start to sprout. Toss a light layer of PREEN or other preemergent herbicide onto flower beds to keep them weed-free.

Many people think using a roller will make a lawn flat, but it actially is compressing it. Think of your spring yard as a wet sponge. Moisture soaks into the roots of the lawn and keeps it strong and green. Ohio State University and Michigan State University scientists agree that you shouldn't tow that heavy roller behind your mower. Rolling your lawn can squash that sponge and lead to compaction. Compacting your soil will stress the plants and cause the grass to die. Toss some extra topsoil in the low spots and seed them instead of trying to flatten the high spots. Those high spots will be gone once the temperatures go up and some of the moisture evaporates.

Contact Kelly Heidbreder at:

kheidbreder@theblade.com