The winter weather is finally breaking in Ohio during the beginning of May. Spring may have started a little later this year, but it is here! So now that the grass has started to turn green and grow, the lawn questions begin to come about. A big question is “when does crabgrass seed germinate?” The simple answer is "well, it depends." Crabgrass does not follow a calendar. Like most other lawn growth topics, it depends on the weather. Ohio and the United States in general can have some pretty unpredictable weather from year to year so there is no exact time of the year for crabgrass germination. Soil temperatures are the main way to tell when germination will begin, but there are some other ways too. The good news is there are different ways you can help get rid of the ugly crabgrass in your yard.

What is Crabgrass?

Crabgrass is a grassy weed that can be found in your yard during the growing season. This weed thrives in summer heat and can be very stubborn. You can find it popping up in the bare spots of grass where soil is exposed as long as it has access to sufficient moisture, nitrogen, and some sunlight. Crabgrass is an annual weed. This means that the crabgrass seeds and spreads in different areas of your yard year after year. Because they are an annual weed, it is important to take care of crabgrass before it takes over your lawn kicking out the beautiful grass.

Is That Crabgrass or What?

Crabgrass is a tricky little weed. It is often hard to tell crabgrass apart from grass or other types of weeds that may appear in your lawn. It comes in many shapes, sizes, and textures because it adapts to your lawn's environmental aspects and growing circumstances, like the amount of water and sunlight available. In the beginning stage, the crabgrass seedlings resemble a miniature corn stalk. Then, the leaves start to branch out.When the crabgrass starts to mature, the plant has thicker blades than grass. These blades are attached to a stem that spread out like a star.

Crabgrass can be small with smooth blades and can grow up to 6 inches or it can be taller (up to 48 inches) with hairy blades. When the crabgrass starts to spread out and take over your lawn, it has long branches that shoot out and turn in sharp angles, making the weed look like crab legs. The crab leg looking branches is where crabgrass got its name from. Maybe you will be able to use that useful trivia on Jeopardy someday.

There is no one color for crabgrass. It can range from light green to a deep dark green so the color is not the best indicator for this weed. Unfortunately, crabgrass is just very sneaky and it is sometimes difficult to identify. If you are unsure, it is best to call a professional. A lawn care company can come out, determine if the "grass" is harmful, and treat it appropriately before it spreads and takes over your lawn.

When Does Crabgrass Seed Germinate?

A large indicator of crabgrass germination is soil temperatures. When daily average soil temperatures reach about 57 to 64 degrees Fahrenheit at one inch deep into the soil, the crabgrass begins to germinate. When the daily average soil temperature becomes about 73 degrees Fahrenheit, all of the crabgrass should be germinated. Soil temperature will differ in certain areas around your yard. If an area of grass is in the shade for most of the day, it will take longer for the soil temperatures to rise and allow for the seeds to germinate. Also, look out for grass next to concrete or sidewalks. The concrete conducts more heat so the soil in the area next to the concrete will heat up faster, allowing for early bloomers.

We can also take a look at the weather to predict crabgrass germination. Unless you put a thermometer in your lawn everyday, it is easier to find out daily air temperature than soil temperature. You can use the Growing Degree Day model where they lay out their prediction for crabgrass germination based on the daily average air temperatures.

Pre-emergent Preventer

The best way to avoid seeing crabgrass all around your yard this year is with pre emergent herbicides. Pre emergent is a treatment that is used to kill the crabgrass before it pops its ugly head out of the soil in the spring. You want to use pre emergent herbicide treatment as close to germination as possible. That is why it is important to try to track down the crabgrass seed growth. If you apply the treatment too early, your lawn will not be protected from the curse of crabgrass throughout the summer. Be sure to space out your crabgrass preventer and seeding. Herbicides will kill the new seeds and not allow the new grass to grow. It is possible to combine two treatments and do fertilizer and pre emergent or a weed and feed mixture to save you some time on your lawn care.

Post-emergent Preventer

Sadly, even after a good application of pre emergent crabgrass preventer, there will still be some sneaky weeds that survive and thrive! You can give your lawn touch ups throughout the summer with post emergent preventers. Applying post emergent herbicides to weeds will take care of the crabgrass. If you see crabgrass anywhere, take care of it quick! Trying to get rid of crabgrass while it is actively growing is much easier than trying to kill one that is at its mature stage. Check your lawn for growing weeds during mowing to ensure you catch the actively growing weeds early.

Other Ways To Prevent Crabgrass

A healthy lawn is a strong lawn. A simple way to keep crabgrass out of your yard is to take care of your lawn and keep it happy. Be sure to keep up on fertilizing. This will give your lawn the right energy to help it block out the weeds. To fill in the bare spots in your lawn where crabgrass likes to hangout, do an aeration treatment and put down some new grass seed to regrow the area's grass.