How to Remove Fertiliser Rust Stains From Concrete

Fertiliser rust stains can be difficult to remove from concrete surfaces such as balconies and driveways. We work so hard to keep the gardens all flourishing by fertilizing it. But sometimes, granular and liquid fertilisers tend to spill on the concrete and cause orangish stains, even though it doesn’t necessarily cause harm to the environment. 

You can remove these unsightly orange stains with a little bit of hard work. Read on to know how to remove the orange fertiliser rust stains from such concrete surfaces. Let us first understand why fertiliser stains concrete.

How Does Fertiliser Stain Concrete?

Fertiliser causes orange rust stains due to the presence of iron in fertilisers. Like other essential minerals such as nitrogen, potassium, magnesium, copper, and zinc, iron is required by plants to grow well. All plant foods and fertilisers contain different amounts of iron.

Sometimes, fertiliser granules get strayed from the grass onto the concrete. When these granules come in contact with water or moisture, iron moves out and stains the concrete. If ignored, the minerals present in the fertiliser can damage and permanently change the color of the concrete.

Once the concrete is stained, it can be difficult to remove them completely. They would not go away by simply scrubbing the floor with water. An acidic solution is the best bet in such cases. These stains are not permanent but it takes some effort to remove them completely. 

Another ingredient in fertilisers apart from iron that causes damage to concrete is ammonium sulfate. It contains nitrogen and is considered a salt. When ammonium sulfate comes in contact with water, it corrodes the concrete due to its acidic properties. Over time, due to erosion and sidewalks lose their structures. 

How To Remove Fertiliser Rust Stains from Concrete?

There are a couple of ways by which you can remove rust stains from concrete. Let us take a detailed look at them. 

White Vinegar Solution

Mix equal parts of clear white vinegar and water and apply this vinegar solution on the stains multiple times to remove them. Vinegar has acidic properties that help to remove rust stains. 

Spray or pour the mixture on the floor. Scrub the stains gently and rinse after a few minutes. Once you are done scrubbing, use a hose to spray the floor with water and rinse off the solution. You may need to repeat this process a couple more times to completely get rid of the stains. 

Lemon Juice

Using lemon juice is a fantastic home remedy to get rid of light rust stains. Pour some lemon juice on the stains and let the floor soak it for a couple of minutes. Take a brush with nylon bristles and scrub the stains away. 

Rinse the area clean with water and repeat this process a few more times to completely remove the stains. The acid in lemon juice helps lighten the stains to a large extent. 

Muriatic Acid

If homemade vinegar solution fails to work on fertiliser rust stains, try hydrochloric or muriatic acid. Mix acid and water in a ratio of 1:1 and apply on the stains. Be careful while using acids as they emit fumes which can burn the lungs if inhaled. Wear a mask and gloves while working with it.  

Acid-based cleaners help dissolve the rust. Most chemical cleaners also contain acids such as oxalic acid and trisodium phosphate. 

Rust Removers

There are various chemical rust removers available in the market that you can use to remove stains. These products are specially designed to remove rust stains and have strong chemicals. Wear a mask and gloves while using such products. 

Rust removers commonly come in a powdered form. Prepare the rust remover solution by mixing it with water. Follow the instructions on the label and mix the product until it feels like a gel. 

Let the rust remover mixture remain on the stains for 15 to 20 minutes before rinsing it off with a hose. Repeat the process and reapply the product until the stains fully come off. Use a pressure washer in case of heavy stains.

A common method we suggest following is soaking a cloth in the product and leaving it on the stains for a couple of hours. Then with a brush and hot soapy water, scrub the stains to make your driveway or path clean and clear.

Tips To Keep in Mind Before Using Rust Removers

Before applying rust removers and other chemical products on concrete, make sure that the surface is clear of dirt and debris. Follow the proper instructions mentioned on the product label and take safety measures to avoid any mishaps. Wear safety gear such as gloves and goggles and work in a ventilated area. 

How To Prevent Fertiliser Rust Stains on Concrete?

If you are applying granular fertiliser to your lawn, be careful and ensure that you apply it only on the grass. After you are done, check the concrete and sweep the granules back to the grass, if any. You can avoid rust stains by simply being a little cautious. 

If you are using a liquid fertiliser, spray it towards the grass and not away from the grass to ensure no spillage on the concrete. Most fertilisers contain little amounts of iron. The iron present in them helps to make the grass healthier and greener. But their only downside is their ability to cause rust stains on the concrete. 

Apart from rust, other elements can damage the concrete. Keep your balconies and driveways clean to avoid these stains. If your concrete is stained, ensure that you clear away all the debris from the floor before applying the commercial cleaning product. 

Final Thoughts

If you have been diligently investing in fertilising your beautiful vegetable or flower garden using liquid fertiliser or are planning to do it soon, follow our tips on removing rust stains and take preventive measures to avoid any damage. Now that you know all about how to remove fertiliser stains from concrete, we hope you will take all precautionary measures to prevent rust stains and follow our tips to clean the stains.