Updated! Crabgrass is all about prevention. It’s hard to get rid of once you have, but easy to prevent it. If you want to prevent crabgrass for a large lawn, it may not be as easy as simply going to Lowe’s or Home Depot. Most crabgrass pre emergent on store shelves only treat a small area: 5,000 square feet to 15,000 square feet. If your lawn is 1-acre, 2-acres, or even bigger, you may consider a crabgrass pre-emergent spray herbicide.
An acre is 43,560 square feet. We have a 2.5-acre yard around our house, so we need to treat 108,900 square feet.
Scotts Crabgrass Preventer and Scotts Turf Builder are great products and have worked well for us in the past. However, that was when our lawns were much, much smaller.
To treat our lawn with Scott’s would take 22 bags of the preventer or 8 large bags of Turf Builder. That would cost $400 and $500 respectively. Not to mention loading/unloading all those bags from the store, into the spreader, etc.
Crabgrass (Digitaria) is an annual. It germinates and dies in the same year. So, every spring, if you can prevent it from coming up at all – you’ll enjoy a crabgrass-free lawn for the summer. That also means your cost to prevent it is an annual cost.
We found a better way. It’s faster, cheaper, and doesn’t require a trip to the store.
Pendulum AquaCap Pre-Emergent Herbicide
2023 Note: We’re trying Prowl H20 this year, since it’s the same active ingredient 
and percentage, but is actually labeled for grazing pastures. We’re not sure if we’ll use a pre-emergent on our horse pastures, but we’d rather have something that was officially approved.
Pendulum AquaCap Pre-Emergent Herbicide comes in liquid form and can be ordered from Amazon, usually for around $175 plus shipping. Even at the full price, this is still a fraction of what we would spend on pellets. BUT – the 2.5 gallons of this lasts us 2 seasons. We calculated that our lawn needed around 1.25 gallons spread over 2.5 acres to be effective.
Towards the end of the season, we did start to see some crabgrass and I believe the label recommends a 2nd application several months after the first. For us, 1 application was good enough. Even at 2 applications a year, the price is still cheaper than the prevention pellets.
Sprayer for Pre-Emergent Herbicide
A sprayer is needed to apply Pendulum AquaCap or any liquid pre-emergent. If you have a large lawn, you’ll probably want a tow-behind spreader that can be pulled by a lawnmower, ATV, or UTV. The size you need depends on how fast you go and how large your lawn is.
We have a 31-gallon NorthStar Tow-Behind Sprayer and found that working at medium speed, with its 10-ft spray radius, that we can spray the 2.5 acres evenly on one 31-gallon tank. That’s helpful since most products (fertilizer, pesticides, and herbicides) are more about coverage than mixed ratio. I.e. it’s not as simple as mixing 2:1, it’s more about applying a certain amount of product to the size of your lawn.
The Northstar Tow-Behind Sprayers come in 21-gallon, 31-gallon, and 41-gallon. We’ve had our 31-gallon version for 4 years now and very few problems. The hand-sprayer is a bit junky and has fallen off a couple of times. The tank, pump, and boom spray have worked well.
Cost Savings with Spray Crabgrass Pre-Emergent Herbicide
Even with a $300 sprayer and $160 pre-emergent, the cost difference is minimal in year one. Subsequent years are considerably less expensive since you already have the spreader. In years 2-4, we’ve averaged $80 per year on pre-emergent for a 2.5-acre lawn.
Sprayers attach to most lawnmowers, ATVs, and UTVs – including Zero-Turn Mowers.
When to Apply Crabgrass Pre Emergent
This needs to be applied before the crabgrass germinates, which is when the soil temps reach 55 to 60 degrees. If the seeds are near the top and the sun is shining on a 55-degree day, they are going to germinate and grow.
I’ve seen recommendations online for May 1 or sometime in April, but anytime I’ve waited that long my results weren’t as good as applying in mid to late March. Here in Michigan, we have a few sporadic days in March that are above 60 – and that causes the crabgrass to ‘wake up’ and grow.
You may also try to time the application of Pendulum AquaCap just before a rain. It’s still cold enough that we don’t have our sprinkler system on yet, or you may not have irrigation. To work, Pendulum AquaCap recommends watering within a few weeks for the best results.
Pendulum AquaCap Tips
- Pendulum AquaCap has the color of curried Indian food and has the same effect on your plastic sprayer as the food does on your Tupperware. It will never be the same.
- If you have light-colored concrete, you’ll want to avoid spraying it on the concrete or it could temporarily stain the surface.
- This is not meant for areas where animals will be feeding (e.g. horse pastures).
- Apply on a day that isn’t windy.
- Some people use blue dye to see where they’ve sprayed, but this seems to be more of a hassle than it’s worth.
- Fill your sprayer with 1/3 water before adding the herbicide. This helps ensure a more mixed solution.
Best Crabgrass Pre Emergent FAQ
What is Crabgrass Pre Emergent?
Crabgrass pre emergent is a type of herbicide that is used to prevent the germination of crabgrass seeds. It is applied to lawns and gardens before the crabgrass has a chance to grow.
When should I apply Crabgrass Pre Emergent?
The best time to apply crabgrass pre emergent is in the spring before the soil temperature reaches 55 degrees Fahrenheit. This is typically around the time when forsythia bushes start to bloom.
How do I apply Crabgrass Pre Emergent?
Crabgrass pre emergent should be applied evenly over the surface of your lawn or garden using a spreader. This can be a pellet spreader or a liquid spreader depending on your pre-emergent. It is important to follow the instructions on the label and apply the correct amount for the size of your lawn or garden.
Can I apply Crabgrass Pre Emergent to a newly seeded lawn?
No, crabgrass pre emergent should not be applied to a newly seeded lawn as it can prevent the grass seeds from germinating.
How long does Crabgrass Pre Emergent last?
Crabgrass pre emergent typically lasts for about 3-4 months. However, this can vary depending on factors such as rainfall, temperature, and soil type.
Will Crabgrass Pre Emergent harm other plants in my lawn or garden?
Crabgrass pre emergent is designed to only target the seeds of crabgrass and should not harm other plants in your lawn or garden. However, it is important to follow the instructions on the label and not apply too much.
Can I apply Crabgrass Pre Emergent after crabgrass has already started to grow?
No, crabgrass pre emergent is only effective at preventing the germination of crabgrass seeds. Once the crabgrass has started to grow, a different type of herbicide or manual removal will be necessary.
Is Crabgrass Pre Emergent safe for pets and children?
Crabgrass pre emergent can be harmful if ingested by pets or children, so it is important to keep them away from the treated area until it has dried. Once it has dried, it should be safe for them to be in the area. However, it is always a good idea to follow the instructions on the label and take appropriate precautions.
