pre-emergent herbicide – Schnarr's Blog

Staying Ahead of Crabgrass

One of the questions I hear every year at this time is “when do I apply crabgrass preventer to my lawn?” The proper timing for application of crabgrass preventer is related more to temperature and weather than the calendar.

Crabgrass is a low growing invasive annual weed. Because it is an annual, and grows from seed each year, the best way to control crabgrass is to us a pre-emergent herbicide to prevent the seed from germinating.

When the temperature of the soil reaches 55 to 60 degrees for several consecutive days, crabgrass seeds begin to germinate. The timing on this can vary widely from year to year and from place to place within your own lawn.

So how does one know when exactly to apply pre-emergent? Well, the most accurate method is to actually “take your lawn’s temperature”, every couple of days, using an instant read probe-type thermometer. But really now, who wants to do that? Another perfectly reasonable method is to watch for the forsythia shrubs (pictured) to bloom. If you time your pre-emergent application to this harbinger of spring you will almost always be well ahead of crabgrass germination. The crabgrass preventers we sell at Schnarr’s will prevent crabgrass and other annual weeds from germinating, and can remain active in the soil for an entire season.

A word or two of caution, if you are seeding your lawn, or you seeded late last fall, most crabgrass preventers will keep grass seed from germinating and damage young grass plants. If this is the case, let us know when you come by to pick up your pre-emergent and we’ll provide a product that can be used when seeding.

Enjoy the spring weather!
Frank

Tim’s Tips – Mid-March

by Tim Wittmaier

Now is a good time to go after cool season weeds in your beds, mainly Henbit and Chickweed. These weeds can take over bare spots of ground. In the warm season, these weeds will die then reappear in the fall.

You can remove weeds by mechanical means such as a garden hoe, or use a chemical. Non-chemical treatments of weeds can work but sometimes are not practical considering the labor needed to treat the area affected. I recommend Roundup Pro because it includes a surfactant that helps the herbicide stick to the weed. You can mix an herbicide using Dawn as surfactant also.

Moles in your lawn are slowed down by pre-emergent herbicides and fertilizer. They don’t like the smell and the chemical odors will deter their mating for awhile. Moles have a very keen sense of smell. For a more permanent mole solution I recommend spring-loaded mole traps.

Milorganite fertilizer has a bonus effect – the smell repels rabbits and deer for awhile.

You can probably reseed lawns earlier than normal this year but it’s still a little early. Wait until the ground temperature is 50 degrees or above through the night. If you have no choice but to seed now, use a rye grass. If you have used any pre-emergent herbicide, wait three weeks to seed or your seed may not come up.

The intermittent warm temperatures may tempt you to accelerate some spring tasks but you still have to be vigilant about the possibility of more freezing temperatures.

Keep an eye out for plants that did not survive the dry winter or have salt damage.