Help There is Grass Growing in My Pool!

This isn’t a fun pool moment. Picture the scene. You’re happily cleaning your fairly new above ground swimming pool getting it ready for the weekend. As you run the vacuum across the pool, you notice something sticking to the bottom. You try to suck it up, but it is stuck. Then you look closer. “What is that? That looks like a blade of grass. Is that growing through the liner?” You let the water settle to get an even better look. “That IS a blade of grass growing through my pool liner!” Your happiness is replaced with a sinking stomach and your mind explores the worst possible scenario with questions like, “How did this happen? Is grass going to grow everywhere in my pool? Can this be fixed? Am I going to need a new liner? Will I have to drain the pool?” With the adrenaline pumping slightly, you stop cleaning the pool and quickly go on the Internet. Through searching the web you eventually find this blog and when you read the next heading, you breathe your first sigh of relief.

Nutgrass Will Not Destroy Your Above Ground Pool Liner

Nutsedge or nutgrass is a persistent weed. When in its growth stage, it grows upward forming a needle-like point that is strong enough to grow through asphalt. A pool liner is no match for the nutgrass as it pushes toward the sun with its super strong point. So the result is it grows straight through the liner of your pool. There can be anywhere from just one or two blades all the way up to a couple hundred blades. This depends on how much nutgrass is in the soil underneath the spot where you have installed the pool.

Usually only a few blades grow through the liner, but there can be more. Over the years I’ve seen extreme cases of nutgrass intrusion that amounted to a hundred or more blades growing everywhere on the bottom of a single pool. It’s a very odd sight when you look into a pool and it has perfectly healthy, green grass growing in the water. I said earlier that nutgrass won’t ruin a liner, but in extreme cases where there are too many blades growing through it’s best to replace the liner. Partly because it’s a lot of work to patch them all and partly because you’ll want to treat the soil underneath so the nutgrass doesn’t reappear.

Getting Rid of Nutgrass in Your Pool

I get it. This is all good info and everything, but you want to know how to fix this. OK, so the first thing
you’ll have to do is drain your pool. JUST KIDDING. You do not have to drain your pool to get rid of nutgrass. The hole the grass has made can be patched underwater.

Here’s what you will need to get rid of nutgrass:

• An underwater vinyl patch kit
• A small pair of clippers
• A dropper used to administer ear-drops or larger syringe needle
• Some liquid weed killer (like Roundup)
• Scissors
• A dive mask and weight belt would be nice
• A bathing suit ’cause you’re going to get wet

So here are 10 steps that explain exactly what to do:

1. Open your patch kit, read the directions and then cut some patches the size of a 50 cent coin using a pair of scissors. Place the vinyl patches and the provided glue on the pool’s top rail so that you can get to them from inside the pool.

2. Fill your syringe or ear dropper with the liquid weed killer (Roundup) and place it on the pool’s top rail next to your patches so that you can again have access to it from inside the pool.

3. Place the clippers, dive mask, and weight belt on the top rail for the same reason.

4. Put on your bathing suit (optional) and get into the pool.

5. Now that you’re in the pool, put on your mask and belt, grab the clippers and swim to where the nutgrass is growing on the bottom.

Real pool guy tip: If you don’t have a weight belt, it will to be harder because your body is going to try to float up while you are on the bottom of the pool. If you have a helper, he/she can gently hold your body down with his/her foot. If you don’t have a helper, emptying your lungs of air by exhaling slowly will keep you on the bottom of the pool more effectively and you won’t float up as much.

6. Once at the site of the grass blade, clip the grass at the base and leave the clippers down there on the spot and return to the surface.

Note: Leaving the clippers on the bottom at the site of the grass blade that you have clipped will ensure that you will find it again when you go back down. It would really suck if you lost the spot.

7. Once you’ve returned to the surface, take one patch, dab some vinyl glue on one side of the patch, fold it in half and take it with you and return to the spot where you have clipped the nutgrass. Also, take the weed killer applicator with you to the bottom.

8. When you get back to the site of the hole, quickly shoot some weed killer into the hole and immediately unfold the patch and press the glued side down over the hole. Repeatedly press the patch in place, making sure it’s nice and flat and sticks to the liner nicely and evenly.

9. Grab your clippers and injector and return to the surface again. You’re done!

10. Pat yourself on the back, because it’s fixed.

There you go. See how easy that was? Now you can go back to getting ready for the weekend’s big pool party. No one will notice that you got all stressed and had to fix the pool, unless you tell them.

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