Get off your ass if you don’t want Crabgrass

crabgrassWhen it comes to lawn care, I probably get more questions on crabgrass treatment than all other lawn care concerns combined. The reason most people struggle with crabgrass control is that they don’t understand what they are dealing with. We at FAM are going to drop some knowledge on you all year long, so that when you walk your neighborhood this summer, you can hold your head high. Let’s face it folks, having the best lawn in town simply makes you a better person than everyone else.

Crabgrass is a summer annual grass weed, which means that it germinates in the spring, grows all summer long and then dies with the first hard frost. That is the one good thing about crabgrass: just because you had it last year, does not mean you are doomed this season. Crabgrass only lives for one year, but before they die, it deposits copious amounts of seed into your soil for next year. We want to stop those seeds from germinating this year.

Natural Prevention

The best way to prevent any type of weed infestation is to maintain a healthy lawn; this is no different with crabgrass. Weeds are like the neighborhood bully, they prey on the skinny and weak, they want the path of least resistance. Crabgrass thrives in warm soil and sunlight; you aren’t likely to see crabgrass grow in areas that are predominantly shady. That is why you see crabgrass growing around the edges of sidewalks because the asphalt heats up the soil in that area faster. Crabgrass also tends to grow in bare spots, in areas where you seeded or maybe need to seed. That’s why I always recommend a fall seeding, and when you do seed in the spring do it as early as possible.

Mowing seems like a pretty simple thing to do, but most people don’t do it correctly. People are obsessed with mowing their lawn too low, this takes away your lawns natural canopy. Mow your lawn higher; this will keep your soil cooler, as it will stop direct sunlight from getting to the ground. The cooler the soil, the less conducive it is to crabgrass. Mowing too short also weakens your lawn, we already talked about how crabgrass likes to prey on the weak. Listen, you aren’t a golf course, you don’t have to mow your lawn likes it’s a fairway at Pebble Beach. Be extremely careful when mowing or weed whacking around your lawn’s edges, the sidewalks, and driveway. Scalping your lawn is an open invitation to crabgrass, you might as well just plant it in your yard yourself. Take the two extra minutes it takes to adjust the wheels of you mower that is in the bed to prevent scalping. There is a reason that you can lower and raise each wheel on your mower individually.

Start watering your lawn early in the year, don’t wait until summer to water. We want to promote deep healthy root growth early, this strengthens your lawn and makes it much harder for crabgrass to establish itself when it germinates. Again a strong and healthy lawn makes it harder for any weed to penetrate your yard. Waiting until your lawn shows signs of stress, means it’s too late. Those conditions give crabgrass the advantage, we want to do whatever we can to create an environment that allows us to block out crabgrass.

Early spring fertilizing is a great way to thicken your lawn and promote growth. Your lawn is going to grow the most in the spring and the fall, not in the hot days of summer. We need to take advantage of the time we can grow our lawns before the crabgrass germinates and when it first begins to sprout. Remember when it gets extremely hot in summer and our lawns stop growing, that is when crabgrass has the advantage. We want to be too healthy by that time for them to ever get a hold on our lawn. It’s why I recommend winterizing your lawn at the end of the year so that there are already nutrients in the soil for the lawn to use when it first comes out of dormancy in early spring.

Applying a Pre-Emergent

When it comes to applying a pre-emergent for crabgrass, timing is everything. Put it down too early and it won’t be effective by the time the seeds germinate, put it down too late and the crabgrass has already sprouted and started taking over the lawn. There are a couple key indicators that will let you know when to put down your application in the spring. The most accurate way to know is by the soil temperature, this will tell you the ideal time to apply your pre-emergent. This doesn’t mean you have to go out and buy a soil thermometer, although it will only cost you about 5 bucks, you can find your areas soil temp in a lot of places. Newspapers, a quick Google search, the state or county agricultural department, a lot of universities will provide you with your area’s soil temp as well. When soil temps start hitting 55 to 60 degrees for about 5 consecutive days, then the crabgrass will begin to germinate. We want to have the emergent down before this happens, so when you see the soil temps break 50 degrees then it’s time to put down your application. Another good indicator is if you see shrubs begin to bloom and trees budding, then soil temps have reached the temperatures that means it’s time to get your pre-emergent down.

I highly recommend Dimension for your pre-emergent, it’s the most effective product on the market.


About 90% of the products sold to the public will be a combination of a fertilizer and crabgrass preventive solution, I have no problem which way you go with it. I personally always put down a fertilizer application along with the pre-emergent, it in no way inhibits its effectiveness. When you are applying it, make sure you put it down evenly, also make sure you are hitting the edges of you lawn, especially around sidewalks and driveways. If you plan on doing some spot seeding or re-seeding I would recommend waiting at least 3 months after the application. Now if you are late and you already have some sprouts of crabgrass, that doesn’t mean that you shouldn’t apply the pre-emergent. Not all seeds germinate at the exact same time and if you could prevent 50% of the seeds from germinating by applying it late, that’s better than not applying it all and giving up on it for the year.

There are post-emergent herbicides that work by killing the actual crabgrass plant. I really don’t have a good recommendation on them because it’s just not an effective way to control the crabgrass in the lawn, it’s a losing battle to use a post-emergent. It’s really hard to not affect the good grass in your lawn in a negative way. You end up having to spot treat your lawn all year long, why not just prevent it in the first place.

The best preventive of any type of weed whether it’s an annual or perennial, a broad-leafed weed or a grass weed is a strong and healthy lawn. We plan on helping all of our readers have the nicest lawns in their neighborhoods, because remember we are simply just better than they are, and it starts with our lawns. You can tell a lot about a man by the way he takes care of his lawn, and you know what they say, “A man that takes care of his lawn, is a man that never leaves a woman unsatisfied.” If you have any lawn care questions or concerns please email us and we will answer them.