Skip to Content

Ironite for Lawn: Is It Harmful? (7 Tips to Use)

Ironite for Lawn: Is It Harmful? (7 Tips to Use)

Ironite is one of the most popular fertilizers on the market. And, why wouldn’t it be? Who wouldn’t love having a fresher and greener lawn? But before using it, you might be having doubts, and rightfully so!

Here, in this post, we’ll discuss everything you need to know about Ironite. Let’s get started!

What is Ironite?

What is Ironite

Image Credit: lawnchick

As its label says, Ironite is a mineral supplement that majorly contains Iron, i.e., 20%, and is often advertised to make your lawn ‘Greener’.

Previously, Ironite was made using recycled mine tailing released from a mine in Arizona. Later, followed by major controversies regarding heavy metal contamination in the fertilizer, around 2005, the site was declared as an EPA superfund site and was closed.

Ironite, today, is owned by Central Garden &Pet Co., through its subsidiary, Pennington.

What Does Ironite Contain?

Before using Ironite, you must know what’s in it! The supplement’s active ingredients are Nitrogen, Urea Nitrogen, Soluble Potash (K2O), Calcium, Sulfur, and of course, Iron. Ironite is also known to contain two toxic ingredients: Lead and Arsenic.

Various testing has been done to find out the contaminants in Ironite. According to the testing done by the state of Minnesota, Ironite contains 6020 parts per million Arsenic and more than 3400 parts per million of Lead.

Similarly, the information provided by the Ironite Products Company published by the Washington State Department of Agriculture shows that the Ironite contains almost 4380 parts per million of Arsenic and 2940 parts per million of Lead.

Though there’s a major concern of all ingredients not being listed on the box, the company claims that the Ironite they sell is safe to use. They explain that the chemical found in the Ironite is tightly bound; thus, it can’t be absorbed all by the plant body and is safe for use.

These claims came in dispute when the testing done by the state of Washington gave the opposite results. The result showed that around 81% of the Lead and 36% of the Arsenic could be absorbed.

Types of Ironite

As suggested by the name Ironite are very rich in Iron. Still, different Ironite formulas are also available, including other nutrients such as Manganese, Potassium, and Nitrogen for other benefits on the lawn.

Now talking about the types of Ironite, there are generally two types of Ironite available in the market: liquid and granular.

  • Liquid Ironite for lawns

It would be best if you always used liquid Ironite with alkaline and sandy soils. It is a fast working formula. It is directly applied to the blades of the leaves, and it goes right into the system. Be careful not to overuse it as it might turn your leaves gray.

  • Granular Ironite for lawns

It is directly applied to the soil. It takes a longer time to show its effect as the molecule needs to be broken down. It also lasts more than the liquid Ironite. If you are using granular Ironite, you must wait for 60-90 days to show its efficiency.

It is the best product for an ideal lawn and is also useful for growing grass in clay soil. It is generally combined with granular fertilizer before application for best results.

Is Ironite Necessary for your Lawn?

If you use Ironite, you might have seen the differences and understood why Ironite could be important for your lawn. Even if you haven’t, the truth is, Iron, along with Zinc and Copper, is vital to the soil. If your soil is Iron deficient, it declines the growth of the plants.

The other benefit of adding Iron to your lawn is to get grass with a dark green color. It is all you need to make your lawn greener, and it was all for which you invested your money.

Another thing you need to understand is that the nutrient that makes your grass green is Nitrogen, and it should be added regularly to your soil. The use of Ironite, which also contains Nitrogen and other micronutrients in its formula, helps in greening your lawn grass by aiding photosynthesis.

When to Put Ironite on the Lawn?

When to Put Ironite on the Lawn

You can simply add Ironite any time of the year on your lawn. But suppose you have any newly planted grass on your lawn. In that case, you must be careful about spraying the Ironite at a cooler temperature because the higher the temperature, the more effect is seen on younger leaves.

The ideal temperature for spraying the Ironite is between 40-80 degrees. So, spring, fall, and winter provide you the best opportunities to spread Ironite on your lawn because of the cooler temperatures.

You must also be careful not to use excessive Ironite on your lawn. You should always seek expert advice if you are not sure of what quantity to use on your lawn.

Is Ironite Harmful?

Prolonged exposure to Arsenic is known to cause a condition in humans known as Chronic Arsenic Toxicity (CAT) or Arsenicosis. Weakness and anemia, chronic lung diseases such as chronic bronchitis, cancers, especially of skin, lung, and urinary bladder, and the list goes on.

Likewise, Lead toxicity is another major issue. It can cause gastrointestinal, hematological, and even neurological dysfunction in both children and adults. Humans are commonly exposed to Lead and Arsenic via water, air, or ingestion.

The worst of all is that chemicals like Arsenic and Lead are known to build up in the soil, thus, increasing in concentration slowly. Carl Rosen, a scientist from the University of Minnesota, used to apply Ironite to his own garden.

And, when the Arsenic amount was measured later, Dr. Rosen’s garden was found to contain around 100 parts per million Aresinc. In contrast, other control gardens were found to have only around 1 part per million Aresinc. This study proves the tendency of Arsenic to build up.

As we see, the harms of using Ironite on the lawn are obvious. So, if you have a child, especially a toddler, who is sure to be spending too much of their time in the lawn playing and rolling, applying Ironite should be a big No-No!

However, on the brighter side, there has been some news that the Ironite has changed from its original product and is very safe for use in crops. The EPA has even allowed the label to include application to the food crops. 

Tips on How to Use Ironite for Your Lawn

To apply Ironite to your lawn, you need to know about proper measures and have good knowledge on the matter. Else, as we’ve discussed before, the harms might outweigh the benefits. Now, let’s discuss how you can use Ironite safely, shall we?

1. Make sure Ironite is your last resort

We’d recommend you not to use Ironite unless it’s essential. If your lawn grass and plants have been showing signs of interveinal chlorosis, i.e., orange coloration around veins, that might be a major indication.

Usually, the soil contains enough Iron for the plants. The problem is that it might be in bound form and unavailable to your lawn grass. You can take a few measures in such cases. Firstly, you can try bringing the soil pH down.

2. How much is too much?

If your lawn soil is iron-deficit, most probably, it will only require around 1/3 pound per every 100 square feet of Ironite. You can add around 1 pound per 100 square feet if you feel necessary.

Remember, using too much Ironite will not make your lawn greener; the grasses instead will turn blackish-green and eventually die.

3. Water once you’re done!

Once you finish applying Ironite to your lawn, make sure you water it thoroughly. Doing so will break down the Ironite granules, and the soil can absorb them with ease.

4. Only 4-10 times per year

The manufacturer’s guide instructs you to use the supplement only four times per year. If you feel necessary, you can up the application time. But, remember not to exceed 10 applications per year.

5. Keep your pets and kids away

Whenever you use mineral supplements such as Ironite, make sure you keep your pets and kids away from the lawn, at least for a few days until the concentration is diluted in the soil.

6. Take proper safety measures

Though the new version of Ironite claims that it isn’t toxic and can even be applied to vegetables, you can’t be too careful. Always wear gloves and a mask whenever you’re spraying the granules. If the Ironite is too dusty, you should even wear your garden goggles.

7. Don’t wash it away; sweep it instead!

Ironite is notorious for staining concrete, paving bricks, and even rocks. So, if you witness any granules on such surfaces, your best response would be to sweep them immediately. The same is the case for clothing.


By now, you know when to use Ironite and how to do so, don’t you? We’ve provided you with every small detail. Now, it’s up to you whether or not you want to use it.

Just make sure that you follow proper safety guidelines and don’t overdo the application. And, most importantly, use only when you have to!

Leave a comment

Your email address will not be published. Required fields are marked *