Torpedo grass, scientifically known as Panicum repens, has widely been referred to as Florida’s problem weed or one of the most serious weeds in Florida.
The plant is native to Asia and Africa, making its first debut in the Americas as a forging crop.
This highly invasive crop spreads through rhizomes, which penetrate deep into the soil, making them much harder to get rid of without numerous and persistent chemical treatments, especially because of its unbelievable levels of resistance and grit.
How do I identify torpedo grass?
Like any other weed, proper identification is the first step to successfully getting rid of them.
This is because some weeds share key features that can easily be confused. Using some methods of weeding might be effective for one weed and not the other, so pay close attention to correctly identify them before applying any measures.
Torpedo grass can grow up to 2.5 feet (0.7m) in height. Their inflorescence is a vertical pinnacle, which grows between 3 and 9 inches (7.5 to 23 cm) long.
The stems are rigid and smooth with hairs and produce thick leaves that are sometimes folded and greyish-green.
So, does torpedo grass die in the winter? This is another way to tell if you are dealing with torpedo grass.
It is a perennial plant which sprouts in February and seeds in July. They are not tolerant of the cold, and they die once it starts to frost in winter.
Now that you know how to identify it, how do you kill torpedo grass?
How do I get rid of torpedo grass?
The best methods may vary depending on where you have a torpedo grass infestation and the season. This article will go into detail about all the variables, so you will know for sure what likely works for you.
1. In lawns
Some lawn grasses are more delicate and susceptible to damage than others.
For the more delicate grass species, you can use a formula with chemicals such as sethoxydim and quinclorac, which are selective, so they will kill torpedo grass without damaging your lawn grass.
So, does Roundup for lawns kill torpedo grass? If your torpedo grass infestation has become aggressive and you do not mind your grass taking a little damage, you can use Roundup, a glyphosate-based herbicide.
2. In flower beds
Because flowers are delicate, it is best to use a selective herbicide such as Fluazifop or Sethoxydim. You must make several applications to ensure you have killed the weed entirely.
If you do not want to keep coming back to apply herbicide, you may opt to use a glyphosate-based weed killer like Roundup, applied directly to the weed.
Unfortunately, you might have to start your flower bed again due to the damage the delicate plants will endure.
3. In a pond
The best regime for torpedo grass infestation of a pond is a four-step method which has proven effective over time.
First, you will need to clear the floating bits of the plant that you can get out. After that, drain the pond completely, and follow up, clearing any other bits that you did not get the first time.
For whatever is left, burn them, and then apply a glyphosate-based herbicide throughout the pond’s interior. You will need several applications to get the weed under control fully, but once it is, you can fill up your pond again.
Natural ways of getting rid of torpedo grass
In addition to all these chemical methods you can use to get rid of torpedo grass, there are still other ways to kill torpedo grass naturally if you do not want to contaminate your soil with chemicals.
1. Baking Soda
The first organic way to eliminate it is using baking soda for torpedo grass. However, evident in how much it dries up the soil, torpedo grass needs a lot of water for survival.
Baking soda is a dehydrating agent that absorbs any moisture in its surroundings. As a result, the torpedo grass will lose moisture and eventually dehydrate, effectively killing it.
When you are sure that the weed is dead, remove it, ensuring that you have also gotten the rhizomes out because this part of the plant is one of its reasons for being so perseverant and will sprout again if left behind.
Many gardeners have asked if vinegar kills torpedo grass. Torpedo grass can survive sudden and rapid changes in ph. However, if the ph. gets too acidic for a period that is too long for the plant to handle, it will die.
If you choose to use vinegar to kill torpedo grass, you should know that it is a non-selective herbicide, so it will kill any other plants it comes into contact with. You can cover your other plants with a tarp to prevent the vinegar from getting to them.
Alternatively, you can apply the vinegar on a day when there is not much wind to prevent wind-borne vinegar from touching your other plants, spraying in the direction of the wind, or simply being careful not to get it on your other plants. If you can’t do this, you might have to kill your plants and start afresh.
Vinegar is a very acidic compound with a ph. of 2-3. When it comes into contact with torpedo grass, it seeps through the membranes and penetrates the cells, eventually causing the plant to die. For this to happen, the vinegar must have been in contact with the plant for a couple of hours.
For this reason, you may need to keep spraying the plant with vinegar every once in a while and even pouring it directly onto the soil, so the weed’s roots can absorb it. You might also need several applications for those particularly resistant patches.
Carla is a student pursuing a B.S in Agricultural Systems Technology. With a passion for landscaping for over 4 years, Carla loves plants. She has previously contributed to several other sites in the space before joining InsightWeeds.