How to remove rust stains from a concrete patio

A rust stain can taint the look of your beautiful patio or driveway. Rust stains come from a variety of sources. Kids leaving their bikes lying on the patio or a metallic tool left out in the rain can transfer rust on the concrete surface and it is usually a challenge to clean.

Rust stains on a concrete patio won’t come off with just plain water and soap. You will need an acidic remedy to effectively tackle the rust. Use a mild acid like vinegar, lemon juice or cream of tartar and combine it with a mild abrasive like salt or baking powder.

Acids for removing rust stains

Acids can remove rust stains from concrete by dissolving the rust, but harsh and strong acids should be avoided because they can damage your patio. You can make inexpensive DIY acidic solutions using a few household products that will do the job perfectly.

The best choices for cleaning your concrete are:

1. Distilled white vinegar, which contains acetic acid
2. Lemon juice contains, containing citric acid
3. Cream of tartar, which contains tartaric acid
4. Hydrogen peroxide
5. Baking soda

Vinegar rust stain remover

Vinegar is acetic acid, which forms during the fermentation of sugar and starch. Not only is vinegar safe enough to be consumed, but it also makes an excellent eco-friendly cleaner, that can be used for many things, including removing rust stains from concrete.

1. Sweep the concrete patio first with a soft broom to remove excess dirt and dust.
2. Put undiluted distilled white vinegar in a spray bottle and spray directly on the rust stains.
3. Leave the vinegar to dissolve the rust, so let it settle about 20 minutes.
4. Using a wire brush while still spraying more vinegar, scrub the area vigorously. Brush until satisfied the rust stain is gone.
5. Use a water hose to rinse the patio and leave to dry.

Use lemon juice or lemonade

Lemon juice has a reputation for being able to handle many stains. The juice from this simple fruit is even tough enough to tackle rust stains on concrete.

1. Boil a gallon of water
2. Squeeze 6 lemons or get 1 cup of lemon juice and mix the juice in the boiling water. If you don’t have fresh lemons, you can even mix 1 packet of unsweetened lemonade into the hot water until it is dissolved.
3. Pour the mixture in a spray bottle and spray directly on the stains. The citric acid in the lemon will dissolve the rust. Allow the lemonade to work on it for some time.
4. For a more powerful approach, you can add a cup of salt to the rust stain patches. Salt makes the lemon juice stronger in the cleaning reaction.
5. Take a hard bristled brush and begin to scrub using force. The stain should be able to come off.
6. Rinse your patio with a water hose.

Baking soda and hydrogen peroxide for rust removal

One of baking soda’s features is that it’s abrasive, which makes it an excellent choice for cleaning rough surfaces like concrete. Hydrogen peroxide breaks down into oxygen and water, which makes a combination of the two effective for rust removal on concrete patios.

1. Cover the patio area with a thick layer of baking soda
2. Pour hydrogen peroxide over the baking soda and allow the paste to work on the rust for about half an hour.
3. Add more hydrogen peroxide to the rust stain, then scrub the concrete area with a wired or hard-bristled brush until the rust stain is gone.
4. Rinse the patio with water.

Baking soda and liquid dish soap, another effective combo

Liquid dishwashing soap can be used for much more than just dishes. When it’s mixed with baking soda to form a paste, it becomes a strong and very effective stain remover that can handle rust on concrete.

1. Pour some dishwashing liquid soap on the stain
2. Spread baking soda plus a bit of hot water on the soap to make a thick paste.
3. Allow the thick paste to work on the stain for about 10 minutes.
4. Scrub the area with a hard or wire-bristled brush until the rust stain is gone.
5. Use a hose to rinse the area with water.

Cream of tartar rust removal

Cream of tartar contains tartaric acid, which is found naturally in fruits like grapes, bananas and citrus, making it a naturally harmless substance. Its acidic property makes it an excellent rust stain remover.

You can buy cream of tartar from a supermarket sold in powder form. If you are an occasional baker, you probably have some in your house already. So get it out and soon the rust stains on your patio should be a thing of the past.

1. Spread the cream of tartar on the stains.
2. Sprinkle hot water on top to form a thick paste. The consistency should be that of a thick gum.
3. Let the paste settle for some time to allow the acid to dissolve the rust.
4. Add more hot water as you now scrub the area with a stiff-bristled brush until the rust stain is gone.
5. Rinse and leave the area to dry.

Frequently asked questions about rust stains

What causes rust to stain?

When metals mix with water the result is a rust stain. So, if you leave metal objects like tools, bikes or patio furniture out on your patio or driveway for a long time where they get wet, the result could be an unsightly rust stain.

Is it possible to remove old rust stains, that have been there for a long time?

Rust stains can be removed no matter how old the stains are, you just have use a little effort and try a few approaches. If vinegar or lemon juice don’t do the trick, try something stronger like hydrogen peroxide or baking soda.

The older the stain, the more powerful the option you should go for. Probably even a combination of two.

What is the best solution for rust stains on the concrete?

Any mild acid is the treatment for rust stains on concrete. It could be lemon juice, cream of tartar, or vinegar. You can also add salt or baking powder to the acids as they are mild abrasives. The combination of a mild acid and mild abrasive will be very effective.

Does bleach remove rust stains in concrete?

It is not a good idea to use bleach to handle rust stains on your concrete. It will make the rust situation worse and over time bleach will destroy the rebar inside your concrete, reducing its life. Stick to mild acids like lemon juice or vinegar, combined with mild abrasives like baking powder or salt.

Wrapping up

Your patio deserves some TLC. A clean stain free driveway or patio is very welcoming and pleasing to the eyes, so if you had given up on those rust stains after trying to remove them several times unsuccessfully; now you have options that are workable.

Also, to avoid the rust build-up, once a week try to give your patio a good scrub using any of the above ingredients, the acids are harmless and will only leave your patio shiny and spotless.