How to Kill Johnson Grass and Keep Your Plants Safe

Are you struggling with Johnson grass in your home garden? Johnson grass is an insidious grass that tends to grow alongside other plants in the garden. 

Scientifically it is known as sorghum halepense. This grass is known to grow out of control since it was first introduced as a forage crop. 

It would help if you learned how to kill Johnson grass or else it might destroy all your crops. There are various ways of dealing with this weed. 

You should know how to control it, how to stop it from spreading, and how to kill it as well.

First, you can prevent it from spreading; secondly, you can remove the plants by hand, and lastly, you can kill it using herbicides. 

We are going to examine each method.

Related Article: How to Get Rid of Virginia Creeper Organically

  • Controlling the Spread of Johnson Grass

Controlling Johnson grass from spreading is one of the initial steps you will want to take to get rid of it. Here are things you can do to stop it from spreading

  • Plow your soil several times a week

Identify areas where this grass often grows and till those areas. Tilling the land frequently eradicates the rhizomes. 

If you till it a few times, the rhizomes that are broken up will continue spreading in your garden.

  • Plow the soil immediately after harvesting

How to Kill Johnson Grass and Keep Your Plants Safe

You need to plow your garden after harvesting because this grass has rhizomes that tend to spread very fast. It’s crucial to plow it immediately as this breaks the rhizomes, and prevents them from spreading.

  • Make use of grass-free seed

Seeds can have Johnson grass in them, and this makes it spread. Ensure that seeds you plant are free of this grass.

You can do this by checking the ingredients section of the packaging of the seeds.

  • Use live-stock feed from Johnson grass

Did you know that your livestock feed might include Johnson grass? The result of this is that the livestock droppings will cause the growth of Johnson grass once they eat that feed. 

Always check the ingredients in your livestock feed before buying it.

  • Clean any tool used on Johnson grass

The problem with Johnson grass is that a trace of it on any equipment can cause it to spread rapidly. If you have any tools used in cutting this weed, ensure that you clean the blades and any other area with clean water and soap.

  • Carefully graze or mow areas infected with Johnson grass

How to Kill Johnson Grass and Keep Your Plants Safe

Do you have livestock? Allow them to graze them in regions that have Johnson grass. This will bring the rhizomes of Johnson plant on top. This will prevent it from spreading to other areas but might take some time.

  • Killing Johnson grass using Organic Methods

If you don’t like using chemicals, you might be wondering if there is any organic method of killing Johnson grass out there. Well, the truth is that there are a couple of ways. 

Let’s check them out.

  • Use white vinegar

Vinegar has many benefits to the human body. It is also used as a natural cleaning agent as well as controlling weeds. 

The best thing about vinegar is that it has a high percentage of acetic acid, which is useful in burning Johnson grass. You need to apply vinegar during the fall when the grass rhizomes are building food reserves. 

You could also put it on the grass when it is still young during spring. Protect other desirable plants nearby by covering them with a tarp or a piece of cloth. 

Do this daily until the grass dies.

  • Hand pulling

You can control Johnson grass from spreading more by hand pulling each plant. Ensure that you get rid of the plant’s rhizomes as they are the ones that allow for spreading.

It is only possible to do this during spring when the soil is moist; otherwise, it’s almost impossible. The U.S Agricultural Department recommends this method in dealing with small infestations in the garden. 

Hold the stem of the grass and grasp it firmly in the middle then pull it out of the soil. You can moisten the soil with water or loosen it using a hand trowel before doing this. 

  • Newspaper Mulch

Newspapers can also kill unwanted Johnson grass as well as improve the growth of your plants. Take 8 to 10 sheets of non-glossy papers and spread them on the affected areas.

You want to ensure that water, air, and sunlight doesn’t reach the plant’s grass by overlapping the edges of nearby sheets by 3-4 inches. 

On the sheets of newspapers, put 2-4 inches of the thick organic layer of mulch so that they weigh them down. 

You can use organic mulch like wood chips. After three to four weeks of doing this, you will notice that the Johnson grass is decomposed.

  • Killing Johnson grass using Herbicides

Herbicides can also kill Johnson grass from your garden. There are many herbicides you can use like Certainty. The best thing about Certainty is that it only kills weeds and doesn’t affect your desired plants.

Measure the amount of Certainty you need and mix it in your sprayer. If your area measures 1,000sq ft, you need to use 1.75-1.25 ounces of this herbicide plus two gallons of water. 

Put them in your sprayer and use a fan nozzle setting to apply it on the Johnson grass.  For best results, you should apply this herbicide to your garden every week or after two weeks until all the Johnson grass is dead.

Johnson grass can be a deadly weed that you need to kill before things get out of hand. For example, it produces toxins like prussic acid that can poison cattle that graze nearby. 

Besides that, it interferes with the proper growth of other desired plants. Now you know how you can get rid of Johnson grass using organic methods or herbicides.

As soon as you notice Johnson grass appearing in your garden, you should immediately take action to prevent it from spreading to the rest of your lawn.  

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