What Does Potassium do for Grass?

By Brian Mounts | Feb 15, 2020
What Does Potassium do for Grass

Potassium is one of the top three essential elements that are needed by all plants including Grass. The other two elements, in case you’re interested, are Nitrogen and Phosphorous. Because of the high amounts in which it is required, it’s a macro-element (which is required in larger amounts) in case of plants! But you must still be wondering about the reason behind this. And above all, you might still ask me, What Does Potassium do for Grass?

Well, hold on for a while, I’m getting to it! We’re going to talk about What Does Potassium do for Grass here at Turf Mechanic in today’s article. So, if you’re wondering about it, please take your time to read this article till the very end. I assure you that there is going to be at least something in this article that you would be able to apply in real. So, are you ready to get started?

What Does Potassium do for Grass?

Now, you might be wondering about what potassium actually does for your grass. After all, What Does Potassium do for Grass? Well, there are quite a few things that it does, actually! Here are some of the chief things that it does for your grass that you might want to know about:

  • Facilitating Plant Development: Potassium is one of the elements that grass needs to grow. So, it facilitates the growth and development of the leaves as well as the stem. It does this by helping in the process of photosynthesis- the process by which plants make food using Air, Sunlight and Water with the help of green Chlorophyll.
  • Improving Immunity: Potassium also helps to make your plant healthier by increasing its immunity. If you’re looking for a healthier lawn, potassium is absolutely essential for your plant!

Quoting TheSpruce:

 Adding soluble potash (K2O) to the soil helps grass withstand stress, drought, and disease. Specifically, potassium helps maintain turgor pressure in the cells of the plant resulting in a positive influence on drought tolerance, cold hardiness, and disease resistance. As a result, potassium deficiencies in turf may cause and increased susceptibility to drought, winter injury, and disease.

  • Xylem-Power Enhancer: Potassium also strengthens the overall water-carrying system of your plant. This ensures that all parts of the plant get enough water and that the plant can remain healthy. Plants without enough potassium often start to look yellowish from lack of water.
  • Develops Roots: In fact, Potassium also takes an active part in root development. Roots are a really important part of just about any plant because they actually collect all the water and minerals from the soil. They also hold the plant firmly in the soil. In fact, roots are important from the environmental perspective too, click here to read more about it.
  • Makes Cell Walls Stronger: Potassium also actively takes a part in making the cell walls of your grass stronger. So, if you want your grass to be a little more hardy, giving it a little extra potassium might just be the choice.

These are the main functions that you might want to know about. However, it is worthwhile to mention here that these are not all the functions that potassium has in your plant. Naturally, there are several other functions, and we can’t really go on to mention all of them- mostly because a lot of them might even be yet to be discovered, you know how science works! However here are a few more you might want to know about. Quoting LawnCare,

Catalyzes iron uptake: Iron is also important for nutrient growth in grass. Having enough potassium in the soil encourages plants to intake iron easier.

Helps absorb protein, starches, and sugar: If the grass is experiencing low levels of potassium, it may have a difficulty absorbing the nutrients it needs to survive.

Potassium is mostly available in soil at pH levels of 5.5 or higher in the form of potassium hydroxide, or potash. When applied to the lawn, it often takes longer to move through the soil and become available to plants. Nevertheless, they remain essential to nurturing healthy grass and should always be checked for through a lawn care analysis. 

Symbols that your grass doesn’t have enough potassium

Potassium deficiency has several symptoms, and trust me when I say this, it’s hard to miss. So, you might want to be on the lookout for these symptoms if you want to ensure that your plant is getting enough of the K (potassium):

  • Young-tree Leaves: Are the edges of your leaves turning yellow? Or is its tip turning purple-ish? That might be a clear symbol of potassium deficiency! You might want to get some potassium fertilizer ASAP in this case!
  • Old-tree Leaves: Older trees are generally a bit more hardy. However, if you notice their leaves to be appearing as if they were burned, that might be a sign of potassium deficiency as well.

Quoting LawnCare:

Soil with low pH levels may also experience potassium deficiency due to the increased acid levels. If you have sandy soil, it is likely that it may experience drops in potassium as it is being leached from the soil. You can add organic material or fertilize to help it retain nutrients better.

What to do if my lawn has these symptoms?

Well, there are quite a few things you might want to do in that case. Following this course would be a recommendable course of action:

  • Firstly, you might actually want to opt for a proper lawn analysis. You can do this own your own, or you can go for a professional- the latter option being always a more preferable one since you do not want to take a chance with your lawn!
  • Next, you might actually want to use fertilizers that contain potassium. Think of it just like any other nutrient- you can use the right fertilizer when your soil doesn’t have enough of it. So, going for a good fertilizer is a great idea if you see any of these symptoms springing up in your lawn.
See my full grass growing guide here for more helpful tips – no opt-in needed.

Is Excess Potassium harmful for my lawn?

Honestly, excess potassium is not really harmful for your lawns. A little excess potassium doesn’t really affect the plants, and it’s pretty water soluble and so it gets washed away. It is worthwhile to mention here, however, that in high concentrations, doses of potassium can have serious effects on human beings as well as animals.

From an environmental view as well, potassium is not considered to be a pollutant. This is mostly so owing to the fact that it does not reduce the air-content in water as much as pollutants to. However, quoting TheSpruce,

An excess of potassium would be relatively harmless to the lawn and the environment, but it would probably also mean an excess of nitrogen and/or phosphorus, both of which can be harmful to the environment and over applying nitrogen fertilizer can be detrimental to the lawn – either through too much top growth or even burning the grass.


So, to sum it all up, Potassium is actually pretty important- and let’s explain it with an example. The symbol of potassium is K, and we use that while chatting as a replacement for “okay”. Potassium, is therefore as important as the word “okay in language.

There are several scenarios we face in day to day life where we need to use the word okay. And this is simply because it’s entirely irreplaceable, just like potassium! And that’s the only thing you need to keep in mind when you think of the work of Potassium in your lawn! It plays a major role, and only potassium can do the job, so you need it, and need it in the right amount in order to have the lush-green lawn of your dreams.

Turf Mechanic is here for you!

Finally, we have reached the end of today’s article. We really hope that you could learn at least something new from this article. Hopefully, you would be able to implement these ideas in real and actually make your lawn even more beautiful!

We thank you from the core of our heart to take your time to read this article till the very end. We understand, however, that you might still have a few questions for us. Please know that Turf Mechanic is always here and is always prepared to serve you. So, if you have anything which you think we might be able to assist you with, please do not hesitate in reaching out to us! We look forward to hearing from you!

Once again, thank you for reading this article till the very end. If you liked this article, we have a great idea for you! You might actually want to check out our other articles! Here are a few to get you started:

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