How to Get Rid of Water Grass

If you have a pond or a pool, then you should be aware of ‘water grass.’ It is a type of weed that grows in many water bodies and can ruin the look and function of water bodies. There are several methods to get rid of water grass, but they may not all work for every person. So, in this guide are some methods and home remedies to eliminate water grass from your pool or pond.

What is water grass and how can you identify it?

Water grass is a type of weed that grows in fresh water and can be very harmful to the environment. It is usually a noxious weed that grows in underground water or near drainage systems but can also be found growing in lawns, gardens, and near ponds. It is a plant that you gather by hand (wear gloves) and burn, as they are very poisonous.

It can create a lot of problems for ponds and pools because it can reduce oxygen levels, which harms fish and other aquatic life. In addition, the weed can also clog up filters and pumps.

Water grass is typically green in color with long slender blades. It often has a feathery appearance and can grow quite tall. The weed typically starts to grow in late spring or early summer and continues to grow until the fall season.

If you are unsure if you have water grass in your pond or pool, there are several ways to identify it. One way is to look for long, green blades sticking out of the water body. You may also see small, white flowers blooming on the weeds. Another way to identify water grass is by its feathery appearance.

What causes water grass?

Water grass is caused by an excess of water in the soil. This can be due to a number of reasons, including over-watering your plants, poor drainage, or rainfall.

How do I know if my plant has water grass?

If you see any green shoots growing in patches on the surface of your soil, then there is a good chance that you have water grass.

Why should you get rid of it?

Water grass can take over the soil in which it grows, crowding out any other plants around it. This means that even if you do not have a problem with water grass right now, there is always a chance that it could show up and take over your lawn or garden in the future.

Water grass can also cause damage to your plants because it competes with them for nutrients and water.

How to get rid of water grass

While the best way to get rid of water grass is to prevent it from ever taking root in the first place, there are a number of ways to get rid of water grass once it has taken hold.

Method one: Manual removal of water grass

This is the simplest and most inexpensive way to eliminate water grass. It involves picking out water grass manually. This method works well in small ponds or pools, but the opposite is true for large ponds or pools.

This can be a difficult and tedious task, but it may be the only option for small ponds or pools. All you need is a rake or net, and you simply have to pull out the weed by hand. Make sure to remove all of the weed so it does not grow back.

How then do you pick out this weed?

You can use a rake to pull it out of the pond; however, when removing it from your pool, you will need a skimmer net since rakes may not be effective in getting rid of all water weeds from your pool.

But how does manual removal work?

When pulling them up with a rake or net, ensure that as much root as possible comes with them so that they don’t regrow again and again after each attempt of removal.

Method two: Use of herbicides to kill water grass

This is a chemical way of getting rid of water grass; it is effective but can be harmful to other aquatic life if not used carefully. Herbicides will kill any plant that comes in contact with it, so take care when using this method. There are several types of herbicides, but the most popular ones for killing water grass are glyphosate and diquat.

If you want the fastest results, then you should use a chemical herbicide. Aquatic herbicides work by killing or stunting the growth of weeds and other plants. They also kill algae in an aquarium or pond. Most aquatic herbicides come as granules for weeds that grow on the surface of the water, as well as liquids for submersed weeds and algae.

How do you use them?

You simply mix the required amount with some water and pour it into the pond or pool where the weed is growing. Be sure to cover all areas where the weed grows for best results.

But what about accidental poisoning of other aquatic life?

If too much herbicide is used, or it spills out into other areas of the pool, then other aquatic life may be poisoned.

How do you avoid this?

You can create a barrier using plastic bottle pieces around the pond or pool to prevent spilling and poisoning of water bodies.

Method three: Use of Aluminium sulphate (Alum) to kill water grass

This is another effective chemical method that kills all aquatic weeds by slowing down their growth rate.

How does it slow down their growth rate?

It does so by raising the pH level in ponds and pools, which causes an increase in nutrient absorption, but reduces photosynthesis from plants.

How exactly do you use aluminium sulfate in killing these weeds?

Mix them with some water and pour over the area where they grow; this will lower the pH level and reduce their growth rate.

How much of alum should you use?

The amount depends on how big your pond is, but in most cases, two tablespoons per square feet of surface area are sufficient to kill water grass effectively.

Method four: Using weevils or beetles to eat up water grass

This method involves using insects that like eating aquatic plants so they can get rid of them for you.

How does it work?

These insects lay eggs inside these weeds when feeding, after which the larvae hatch out and begin feeding on the weed itself until it dies off completely since all nutrients have been used up.

How do you introduce these beetles into your pond or pool?

You can buy them from a local pet store or online and release them into the pond or pool.

How many do you need?

Depending on the size of your pond or pool, anywhere from 500-5000 beetles should be effective in getting rid of water grass.

Method five: Using a biological control agent to kill water grass

This is a safe and environmentally friendly way of getting rid of aquatic weeds, but it may take some time before results are seen. It involves using a living organism to eat up these plants; an example is duckweed which feeds on algae and other small aquatic plants.

How does it work?

The ducks that feed on the weed will excrete their droppings back into the water body, which will contain eggs of new weevils/beetles that will hatch and eat up the weed.

How long does this take?

It may take a few weeks or months for all the weed to be eaten up, but it is a safe and effective way of getting rid of them without using any chemicals.

How can you prevent water grass?

Before the water grass establishes itself on your property, you can follow these tips to prevent it from growing on your property.

  1. Keep the soil pH around neutral (between six and seven).
  2. Mow frequently at two-to-three inches tall with sharp blades. Make sure you keep your lawn mowed at all times to prevent water grass from growing on it.
  3. Make sure to get rid of any water grass that is currently around your home or business, as it can spread quickly in just a few days.
  4. Water grasses produce seeds, which make it very easy for them to grow back after being removed. Make sure to get rid of them permanently.
  5. You should also consider using a weed killer that is designed especially for water grasses so that the weed will not grow back in a few days or weeks.

Frequently Asked Questions

Is crabgrass and water grass the same thing?

No, crabgrass and water grass are not the same. Crabgrass is an annual weed that typically grows in the spring, while water grass can be an annual or perennial weed that typically appears in late summer or early fall.

How often do I need to treat my lawn for water grass?

If you are using an herbicide to treat your lawn for water grass, you will need to apply it according to the label directions.


So that is how you get rid of water grass. By following the methods stated above, you can easily get rid of water grass. Also, using these tips, you can prevent your grass from being overrun by water grass.