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Getting Rid of Crabgrass

Getting Rid of Crabgrass

Crabgrass is invasive and can be a big problem for many gardeners. This guide is about getting rid of crabgrass.

     

Solutions

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Article: Organic Solutions for Crabgrass

hands removing crabgrass from lawn with weeding tool

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.

The Facts on Crabgrass

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.

Preventing Germination

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.


Note: CGM also acts like a pre-emergent on grass seed, so don't use it on lawns you plan to seed.

Pulling Young Plants

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.

Defense by Way of a Healthy Lawn

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.

  • Use a lawn fertilizer with at least half of its nitrogen in a slow-release form. For a 1,000 square-foot lawn, use less than 3 pounds of nitrogen annually. If you're using a "weed and feed" like CGM to treat crabgrass, no additional fertilizer applications are necessary.
  • Always set your mower to at least one inch higher than the settings recommended for the type of grass you're growing. Mowing grass too short stresses turf grass, and leaves your lawn vulnerable to crabgrass and other weeds. Always keep the lawn mower blades sharp so they cut the grass cleanly. Leave grass clippings on the lawn to act as a natural fertilizer.
  • Weeds tend to pioneer areas where the soil has become too compacted for grass roots to breathe. If your yard consists of heavy, clay soils or is prone to compaction, remove thatch each fall and core-aerate your soil at least once per year.
  • Fall is the ideal time to reseed patchy or damaged areas of your lawn. The days are warm, the nights are cool, and there's plenty of morning dew on the ground to help keep seeds moist until they germinate.
  • A thorough watering once a week (maybe twice in sandy soil) encourages grass roots to grow deep, and leaves your lawn less vulnerable to drought.

By Ellen Brown

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Questions

Here are questions related to Getting Rid of Crabgrass.

Question: Home Remedy for Crabgrass

What is the mixture of vinegar and soap for killing crabgrass?

jimdigital


Most Recent Answer

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.

Question: What Do I have... Crabgrass?

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


Most Recent Answer

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.

Question: Getting Rid of Crabgrass

Question:

What is the best and easiest method for getting rid of crabgrass? This year is probably too late to do anything. What should I do for next year? My lawn was over run with crabgrass this year more than any other year.

Hardiness Zone: 5b

Vanet from Saugerties, NY

Answer:

Vanet,

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.

Ellen

By Ellen Brown


Most Recent Answer

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.
good luck

Question: Getting Rid of Crabgrass

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.

Question: Crabgrass Killer

I am looking for a homemade crabgrass killer.

Hardiness Zone: 6a

Tom from Danville, IL


Most Recent Answer

By (Guest Post)07/12/2008

Boiling water will kill off grass too if your crabgrass is in the lawn.

Question: Canadian Grass That Discourages Crabgrass

Question:

I have heard that there is a type of Canadian grass that produces a thick, lush, and hardy lawn. It is supposed to crowd out crabgrass. What is the name of it and where is the best place or website to purchase it at?

Hardiness Zone: 6a

Vanet from Saugerties, NY

Answer:

Vanet,

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).

Good luck!
Ellen

By Ellen Brown


Most Recent Answer

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!

Question: Getting Rid of Crab Grass

I need a recipe for crab grass control.

Hardiness Zone: 9a

By Jboggs2 from Hudson, FL


Most Recent Answer

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.

Question: Killing Invasive Grasses

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

Archives

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.

Archive: Get Rid of Crabgrass?

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


We Use Vinegar

We use vinegar on all our weeds. We mix vinegar and a small amount of dishwashing liquid (to help it stick to the weed) and spray it on crabgrass and weeds. It's cheap and I'm also very wary of chemicals with 4 kids and pets. (04/26/2004)

By Ann

How?

How do you apply it with an sprayer, do you attach to the hose? And what quantities do you use. Great idea because I won't use chemicals either & my yard is being taken over by weeds. (04/26/2004)

By Vicki

Roundup

If you're OK with chemicals, RoundUp is the best herbicide for weeds or any unwanted vegetation. Otherwise, vinegar or salt solution will work, but may make the soil inhospitable to anything for a while. (04/26/2004)

Are you sure it's crabgrass?

Are you sure it's crabgrass? If it stands straight up it isn't crabgrass; probably what is referred to as foxtail or goosegrass. Roundup or vinegar are both okay to use but will kill any grass you spray it on too. (04/26/2004)

By guest

Use a Sprayer

Vicki, To spray the vinegar we use a sprayer from the hardware store. It has a large plastic container that holds a gallon or more and has a short hose and a pump to build up pressure so you can spray it from the hose. Just put the vinegar and dish washing liquid in the plastic container. Most people use the same thing for regular weed killer. (04/28/2004)

Regarding the Vinegar and Soap

As a chemist, I wouldn't recommend adding soap to the vinegar when the intended use is as a herbicide. The acedic acid is the active agent here and soap is a base which just reduces or neutralizes the acidic strength. A mild spray will "stick" well enough. The acid will continue acting even when "dry." I might also add that vinegar is an excellent relief for insect stings & bites as well as sunburn. (06/14/2004)

By Dr. Jose

Crabgrass From Our Landscapers

We had crabgrass last year but not as bad as this year. Our entire lawn is mostly crabgrass. Our neighbors don't have crabgrass so it is not coming from them. I think it came from our landscaping company that cuts several of his customers lawns and one or more of them have crabgrass. Exactly where he started cutting in our yard this year is exactly where the crabgrass started brand new. We are going to work hard at getting rid of it still this year but next year we may try cutting our own grass. (08/02/2005)

Canadian Green Grass

The best way to kill crabgrass and any weed that may grow in your yard search the web for Canadian Green Grass. This seed works wornders. It survives drought, resists lawn infections, and it kills off any weeds and squeezes out the crabgrass. We just planted new seed last year in the front lawn. And I saw some of this grass seed in a magazine so i ordered some for the back lawn to overseed. It turned out that the back lawn was better looking than the front lawn. You really need to try this, the best part being its cheaper than the ordinary grass seed. Just try it and i guarantee you wont be disappointed. (04/14/2006)

By Matt Gill