, Newburyport, MA

April 17, 2013

Tim's Tips: Cures for crabgrass

Tim's Tips
Tim Lamprey

---- — The weather is slowly warming up. On Sunday, as I was outside at the store filling a propane tank for a customer, it began to rain just a bit and then some sleet began to fall. I suppose this is normal for April. As the old saying goes, “April showers bring May flowers.” I guess that fits this year!

The forsythia bushes are beginning to bloom in many areas. As the forsythia finish flowering, be sure to apply crabgrass control to your lawn. The forsythia and the crabgrass have something in common. The soil temperature that makes the forsythia flower is close to the temperatures that makes the crabgrass seed start to sprout. All of the crabgrass controls that you put down now will kill the crabgrass seed as they sprout. This control method is referred to as preemergent control.

There are basically three types of preemergent crabgrass control. The most commonly found crabgrass control lasts about 14 weeks in the soil. It is very effective. Unfortunately, it is also effective at killing grass seed. If you seeded your lawn last fall, this product will harm it.

There is another product that uses a different chemical; it will kill the crabgrass seed but won’t prevent the grass seed from growing.

This is also the product you should use if you seeded the lawn last fall.

An organic control, called corn gluten, will kill crabgrass seed and the grass seed. However, it only lasts in the soil for about four weeks, so it will allow you to control the crabgrass organically, and still have time to apply seed before the hot weather arrives.

All of the preemergent control products should be put down when you have completed your raking.

The reason is that these products form a barrier on the surface of the soil that kills the crabgrass seed. If you apply the product and then rake, the barrier will break. The crabgrass seed will sprout and then become established in your lawn.

Some of you may have purchased new homes since last fall and may not have crabgrass. You can apply a fertilizer to your lawn, and if crabgrass does show up later in the season, you can apply crabgrass control after the plants have grown.

This product is a liquid that you spray onto the young crabgrass plants. This product should be applied before the crabgrass plants get too big.

That time is usually some time in mid- to late July. If you wait to apply the product in late summer, the crabgrass is so big that the spray is ineffective.

Well, that may be more than you ever thought you would want to know about crabgrass. As always, stop by the store if you have questions and we will be glad to help you.

Well, that’s all for this week. I’ll talk to you again next week.


Tim Lamprey is the owner of Harbor Garden Center on Route 1 in Salisbury. His website is Do you have questions for Tim? Send them to, and he will answer them in upcoming columns.