Crabgrass is invasive and can be a big problem for many gardeners. This guide is about getting rid of crabgrass.
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Crabgrass can be relentless. Because it grows fast and tends to thrive in hostile conditions, it can quickly turn your lawn into a tangled patch of weeds, if not kept under control. Here are a couple of organic solutions for fighting crabgrass that are easy, safe, and effective.
Different species of crabgrass are found throughout the United States and southern Canada. These annual weeds bloom on terminal spikes from July through September and can grow from 15 inches to 3 feet tall. Crabgrass stems grow upright or form a dense mat on the ground. The leaves are either hairy or smooth (depending on the species); a 1/4 inch wide, and have an elongated shape.
Next to turf grass, crabgrass looks light bluish green in color. Problems usually start along driveways and walkways, where heat and poor soil discourages turf grass from growing. Because crabgrass reproduces both by seed and from rooted-stems on top of the soil, it doesn't take long for crabgrass to quickly overwhelm your lawn.
The most effective way to treat crabgrass is to prevent it from germinating in the first place. A great organic "weed and feed" product that works as a pre-emergent herbicide on crabgrass is corn gluten meal (CGM). CGM is a natural by-product of commercial corn milling that contains corn protein. This protein acts like an herbicide by creating a chemical barrier at the soil's surface that prevents weeds from sprouting.
In addition to working on crabgrass seeds, research has shown that CGM is also effective at controlling the seeds of chickweed and dandelions. CGM is completely safe and poses no health risks to people or animals. In fact, because it is 60% protein, it is often used in livestock feed and pet foods. As an added bonus, CMG is also 10% nitrogen by weight, which is your lawn's favorite kind of fertilizer.
Where to buy it: CGM is available in both powdered and pelleted forms. Look for it at farm and feed stores, county co-ops, and places that sell garden supplies.
How and when to apply it: Timing is critical to the success of using CGM, because it doesn't work once seedlings emerge. Apply a first round in late April or early May (when surface soil temperatures reach about 55 degrees F), and a second application around mid-August. Spread the product evenly across your lawn at a rate of approximately 20 pounds per 1,000 square feet. Water it in lightly in order to activate it.
You can expect CGM to remain effective for 5 to 6 weeks each time you apply it. Although CGM will start working right away, don't expect to see immediate results. It takes about 4 years of annual applications to achieve complete results.
Pulling young plants out of the ground while in an early stage of development is a surprisingly effective means of control. Simply pull the plants up (stem, roots and all) before it has a chance to set seed.
What to look for: If you spot crabgrass seedlings with two or three leaves, or mature plants with a slender, green seed head that is still tightly closed against the leaves, go ahead and pull it up. If the seed head appears splayed open, however, leave it alone. Otherwise, you'll just scatter thousands of tiny crabgrass seeds all over the lawn. It's better to wait until spring and treat the affected area with a pre-emergent like CGM.
When to do it: Pull out crabgrass as soon as you spot it. Young plants leave only a small hole in your turf, which will quickly fill in with grass.
In reality, the most effective way to control crabgrass is to let your lawn do it for you. A thick, healthy lawn easily crowds out weeds, and creates a dense enough cover to prevent weed seeds from sprouting.
By Ellen Brown
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Here are questions related to Getting Rid of Crabgrass.
What is the mixture of vinegar and soap for killing crabgrass?
By Amanda (Guest Post)04/24/2006
For St. Augustine grass you can use organic crabgrass killers. Just do a google search and you'll find the products.
Hi, I have some sort of grass and I don't know what it is. It has leaves that are 7/16 of an inch wide and has lines in it. The stem of the grass is really stiff or hard and it grows a lot faster than my other grass. It also has a lighter color than my other grass (fescue). Can you please help me out on what it is and how I can get rid of it.
Diana from Michigan
By margaret (Guest Post)05/06/2007
Help! I put down dandilion killer by scotts a week ago, but I have alot of crabgrass. Can I now put down step one of scotts lawn care called turf builder with crabgrass control.
Hardiness Zone: 5b
Vanet from Saugerties, NY
I cannot think of any easy solutions to controlling crabgrass, and I'm not sure a person can hope to ever get rid of it completely. Even when using pre-emergent herbicides, it seems to come back eventually. The first thing that I would suggest is to raise the height of your lawn mower blades to 3 inches. This will support the healthy growth of turf grass and leaves less room for crabgrass seeds to take hold.
For long-term control, I would recommend applying corn meal gluten. This is an all natural by-product of milling corn that acts are a pre-emergent for controlling crabgrass, barnyard grass, foxtail, dandelion, lambs quarters, pigweed, purslane, smartweed and others. If applied once in mid spring (around the time the lilacs bloom) and again in mid August, you should catch two different flushes of crabgrass. A third flush will probably be ready to germinate just in time to be killed off by frost. Corn meal gluten should not be used if you're trying to establish a lawn, because it prevents regular grass seed from sprouting too. If you apply this at a rate of approximately 20 lbs per 1000 sq. ft. the first year, you should see at least a 40-50% reduction in crabgrass. Control will continue to improve each year with successive use.
By Ellen Brown
By Laura Justice08/28/2006
I think the men mowing also "seeded" my yard-- however I made it worse by agreeing to "scalping" in preparation for summer growth. Will never do that again. The grass didn't have the strength to fight off the weed seeds. The other thing I did was insist the height of my grass to be at least 3 inches before mowing-- we'll find out if mine is OK next spring.
Does anyone out there know a home remedy for killing crabgrass? I have used fertilizer with weed prevent in March, and also baking soda recently, but soda kills the grass, too! Crabgrass is taking over my lawns and my life. I do not know what else to try. Help me.
Thanks, The Crabgrass Lady
By Lillian S.
I am looking for a homemade crabgrass killer.
Hardiness Zone: 6a
Tom from Danville, IL
By (Guest Post)07/12/2008
Boiling water will kill off grass too if your crabgrass is in the lawn.
Hardiness Zone: 6a
Vanet from Saugerties, NY
Are you talking about Canada Green Grass? http://www.seenontvproducts.net/...canada%20grass&OVMTC=standard
If so, I would advise you to check out what others are saying on this forum before spending your money: http://turfgrass.com/ubb/Forum5/HTML/000002-2.html
It sounds to me like this particular mix is quite the wonder grass. I'm sure this mix could work under the right conditions, but whether or not your site has the right conditions is something you'll have to research. Try to find out if someone on this forum has grown it successfully where you live.
A good mixture of grass seed for lawns in your zone will probably contain roughly 50% Kentucky bluegrass, 30-40% red fescue, and 10 to 20% perennial ryegrass. A diverse mixture is important. Most turf diseases go after one type of grass so a mixture helps to ensure that at least some of your lawn will remain protected should the worst happen. Look for high-quality mixes. They may cost a bit more, but you're likely to get what you pay for. Less expensive mixes have a lower rate of germination and are more likely to contain unwanted types of seeds (weeds).
By Ellen Brown
By sh (Guest Post)10/31/2006
Don't know if this is the grass you're referring to, or if it would work in your zone, but down here (Texas) we have something called "centipede grass" that crowds out the weeds and makes a pretty lawn. Hope this helps!
I need a recipe for crab grass control.
Hardiness Zone: 9a
By Jboggs2 from Hudson, FL
By kathleen williams09/16/2009
Cover it with plastic for a few weeks. This will work for any kind of grass you don't like. Also search for your question, good luck.
Does anyone know of an effective, non-toxic way to kill invasive grasses such as Bermuda and Crabgrass? I know that Round-Up kills it, but it is highly toxic and very harmful to the environment.
By DP from Las Vegas, NV
Thrifty Fun has been around so long that many of our pages have been reset several times. Archives are older versions of the page and the feedback that was provided then.
Can anyone tell me how to get rid of crabgrass? We have tried so many different things on it and we just can't seem to get rid of it. It is covering a big portion of our yard.
Brenda from Missouri
By Dr. Jose
By Matt Gill