How to get rid of johnson grass? Johnson grass is a troublesome weed that not only displaces pasture and hay grasses but it can tunnel into the rhizomes of your forage crops as well.
It grows from seeds and turion in the late spring, but its most notable appears in May from its stolon.
Its smooth leaves have a prominent white mid vein, and young plants resemble sorghum or Sudan grass, so it’s important to keep an eye out for these weeds!
The seeds are 3 to 5 mm long with an oval-shaped body that is primarily brownish-red; although some seedlings may be tan or dark red typically, this makes them easier to identify than mature Johnson Grass Plants.
How To Get Rid Of Johnson Grass
Johnson grass is a type of grain Sorghum, happens to be exact, that has acted as a pest for ranchers since its introduction.
Many states require homeowners to manage Johnson grass because it’s an invasive plant and weed.
It can come in several different varieties that all need special attention when it comes down to knowing how you’re going to manage them.
Many times, herbicides can control Johnson grass infestations.
However, they still often combine Johnson grass programs with other management methods because the perennial nature of the species usually makes it a complex problem.
1. Newspaper Coverage
Another way to deal with Johnson grass that tried to invade your garden beds is to cover them up while they’re still young.
Spread some paper over the soil and watch as the grass dies away, unable to get any sunlight – or grow any more – without anything to compost.
Within a few weeks, you’ll be able to mow it off (and not have to worry about trying to remove the stalks). This method should take around 2-4 weeks for the Johnson’s weed problem in your yard to disappear.
If needed, you may want to place some additional weight on top of your newspaper so that it doesn’t up blow away in a storm.
2. Flooding with water
To ensure that the Johnson grass is completely eradicated, one can pour about 2 inches of water into an area where the rhizomes grow at ground level.
Since they are still under their soil, they won’t absorb water through their shoots because they are closed and will die after a while.
The plant’s underground roots do not usually go deeper than 15 cm, and therefore, it is better to flood them with the desired amount of water for a month to drown them.
Hydro seeding is most useful for lawns and environments with large areas of visible grass; however, it may not be as successful in settings where large trees or bushes are overgrowing the space.
3. Remove the grass
Hand removal of Johnson grass is a very labor-intensive technique that can be effective.
One trick to remember is that concentrated glyphosate or another herbicide howitzer works well in spot-treating the tops of individual Johnson grass plants without removing the rhizomes.
However, extensive hand removal will undoubtedly leave ‘’giant-sized clumps of the plant intact, which means that you’ll likely have to make another visit for multiple killing seasons.
5. Chemical Spray
Chemical methods can be used for fast-acting methods to kill Johnson grass. Two options are recommended: post-emergence herbicides and glyphosate.
Post-emergence herbicides like 2% Roundup or a nonselective weed killer that contains glyphosate are standard ways to control this invasive herb.
The Illinois Natural History Survey recommends treating Johnson grass in June with 2% Roundup, a powerful herbicide containing glyphosate.
Glyphosate is best suited to control the dense and widespread clusters of this weed, as well as patches of it that are more controlled and managed.
6. Organic approaches
Killing Johnson’s weeds without harming other plants is a challenge, but there are natural ways to do it that don’t require any chemicals.
Unless the surrounding plant life is severely damaged from the use of these chemicals, you can allow the weed to grow for several weeks and then cultivate it out of your garden during one session.
This will kill off some of the weed roots leaving healthy ones behind. As with anything else that may or may not be harmful to your plants, you should never spray them directly with any chemicals (in this case, vinegar).
Also, be sure not to spray herbicides over other nearby plants because they can adversely affect them as well – only use them when necessary in isolated locations where Johnson weed infestation is a problem.
Which is the best time to kill Johnson grass?
The right time to harvest in autumn. Utilizing herbicides in conjunction with physical removal is the best way of dealing with this weed’s invasive rhizomes and seed heads.
How to get rid of Johnson grass and not Bermuda grass?
We recommend using the Certainty Herbicide, formulated to treat Johnson grass and other perennial and annual herbs.
The Security Herbicide is a selective post-emergence herbicide, meaning that it targets only the weeds on your property that are listed on the label, so you can be sure that none of your desirable plants will be harmed.