How to Lower Phosphorous in Lawn

How to Lower Phosphorous in Lawn

Phosphorous is an integral ingredient in fertilizer and is used in lawns to promote strong root growth. It makes your grass greener, healthier and stronger. However, when applied in excess phosphorous not only damages your lawn but also pollutes the surrounding environment.

It’s essential, therefore, that you apply the right amounts of phosphorous on your lawn to promote growth while minimizing the damage caused by its excess. On that note, this article will discuss how to lower phosphorous in lawns, signs of excess phosphorus, and how to avoid excessive application.

Signs of Excess Phosphorous In Lawn

Excessive phosphorous in lawn manifests itself in several ways.

The most evident one is dead patches on your lawn. As the phosphorous works its way into the soil, it has an adverse effect on your lawn’s root system.

It interferes with the plant’s absorption of iron, manganese, and zinc, all vital nutrients. As a result, the grass is unable to absorb sufficient nutrients and hence, fails to thrive. Dead patches appear when the roots are dying or dead completely.

When you notice such patches in your lawn, treat them immediately because allowing the problem to fester can result in irreparable damage. Other signs of high phosphorous content include yellowing of leaves and thinning of grass.

Lawn grasses, particularly St. Augustine grass, thrive in areas with high levels of iron and zinc. The deficiency of such critical nutrients due to high phosphorus levels can lead to the yellowing of the leaves.

If you notice this happening in your lawn, make sure there is enough iron and zinc in the soil and if not, apply it as soon as possible.

How to Lower Phosphorous in Lawn

1. Avoid Further Phosphorus Applications

One of the main reasons for excess phosphorous in lawns is poor application. When you spread fertilizer too thickly, your grass absorbs it all at once instead of slowly over time. This sudden intake produces lush growth, eventually, wither, and dies due to a lack of nutrients.

To avoid this situation, make sure you apply fertilizers only during the recommended time. You can find this information in the product’s package itself or a lawn care book. If you’re using fertilizer for the first time, do some research to determine your soil type and apply it.

2. Eliminate Organic Manure

Organic manure such as animal dung, compost, and kitchen waste are excellent sources of nitrogen, phosphorous and other nutrients.

However, if you spread too much of it on your lawn in one go, the soil may become saturated, which not only makes it difficult for your grass to absorb nutrients but also leads to excess phosphorus.

Therefore, regulating how much organic manure to apply on your lawn can help reduce the phosphorous content.

3. Apply Foliar Iron and Zinc

Iron and zinc are the two most vulnerable nutrients when it comes to excess phosphorous. However, just adding iron and zinc into the soil isn’t enough to balance out the imbalance.

This is especially true because the excess phosphorous can prevent the grass from absorbing these nutrients.

Moreover, applying iron to soil rapidly ties up alkaline phosphates, making it less effective. However, the application of these nutrients in their natural form through the foliage is more effective.

How to Avoid Excess Phosphorus Application in Lawn

To avoid applying unnecessary phosphorous to your lawn, you must first determine the current phosphorous levels and pH in the soil. Test these periodically after determining if more or less are required for a healthy lawn.

Most phosphorous tests require a sample of soil to test its level. The easiest way to collect the sample is by scraping a small portion from the surface or using push-type testers that allow you to scrape only a few millimeters into the ground.

Take care to avoid getting any grass, roots, leaves, or anything else in the sample, as they can corrupt data and result in inaccurate results.

While it is tempting to rely on the results from a garden center, avoid doing so as they offer general guidelines that may not apply to your lawn. Moreover, soil samples are inexpensive and easy to do at home.

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How to Raise Phosphorous in Lawn

Now that you know how to lower phosphorous, you may be wondering if the soil can become too low in phosphorous. Even though this happens rarely, it can happen if all other nutrients are present but phosphorous falls short.

To raise phosphorous levels in your lawn, you will need to add MOLASSES or bone meal and top with a thick layer of organic matter such as peat moss.

If your soil is damp, let it dry out completely before applying these materials.

Although it may seem counter-intuitive to add materials higher in phosphorous than your current soil, remember that the grass can only absorb these nutrients if they’re present.

Additionally, it would be best to take care not to overdo it when adding this material, as too much can cause excess phosphorus and acidic soils.

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How to Lower Phosphorus in Lawn (FAQs)

How do I know if My Soil has too Much Phosphorus?

To know if your soil has too much phosphorus, it’s essential to take a soil test. Most kits are easily available for purchase at your local garden center or online store, and they’re easy to use.

What happens if a plant has too much phosphorus?

If a plant has too much phosphorus, it can lead to iron deficiency and brittle growth. Lack of phosphorous results in pale green to yellowish leaves, especially on the tip of the grass blades.

How do I make sure that my soil has enough phosphorus?

You should amend your soil with aged manure, peat moss, and vegetation products that are high in phosphorus.

Although not the most crucial component in lawn care, excess phosphorous may cause damage to your grass and soil. By monitoring how much phosphorous you introduce into your yard, you can maintain healthy levels and keep your lawn looking great.

Understanding how to lower phosphorus in lawn is one of the best ways to ensure that your lawn stays vibrant.

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  • Ricky

    Hi, I’m Ricky. I’ve been involved in lawn care and landscaping from when I was 15. To be honest, I didn’t like the idea of pushing mowers, collecting grass clippings, and maintaining flowerbeds at the time. But having seem the passion my parents had for gardening and outdoors and the effort they put in maintaining the health and beauty of our landscape, I couldn’t help but not only admire their hard work but also I became a part of it. As someone who loves to spend time with nature’s best, I find myself learning a lot more about gardening and outdoors on a daily basis. Not to mention I love to share the knowledge I’ve gathered over the years with my readers at We Mow Dallas. To be clear, I don’t have a Master’s degree in gardening or anything like that. Everything I’ve learned about gardening, landscaping, and lawn care spring from passion and engagement with my parents. And with a ton of free information out there, plus the ability to run tests and determine what works best for lawn care and landscaping, every day is an opportunity to learn and implement something new. My goal with We Mow Dallas is to teach you exactly how to maintain your lawn and landscape. And since I walk the talk in reality, you shouldn’t hesitate to join me in this wonderful world of landscaping and lawn care. K Beatrice

1 thought on “<strong>How to Lower Phosphorous in Lawn</strong>”

  1. Joe Roper, Jr.

    I have had 2 soil tests done by UGA last year and this year and phosphorous level is high.
    My bermuda grass has small patches of slightly tan brown coloration. But otherwise looks healthy.
    This year I switched to organic fertizer (chicken manure).
    I aerated and applied humic acid in late spring.
    This year I applied a top dressing of peat moss and cow manure.
    So how do I lower the phosphorous level in the soil?

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