Terracotta pots give the most beautiful earthen look and feel to your plants. The additional advantages of these pots include being natural, porous, and absorbing excess moisture from the soil, which improves your plant’s overall health. However, after a while, terracotta pots develop white residue. In this post I will explain the reason behind this residue and quick, easy methods to clean terracotta pots.
What is the white residue on terracotta pots?
1) Hard Water Deposits
One of the reasons the white deposits appear on your terracotta pots (terra cotta pots) is when you water the plants with hard water (tap water in most places). Hard water contains salts and minerals such as calcium. As the water evaporates, these soluble salts are left behind as white salt marks. It is similar to the white crust left on your shower head.
2) Fertilizer Leftover
If your tap water is not hard, your soil fertilizer is the likely cause of the white residue. Fertilizers contains minerals. Since terracotta pots are porous, the minerals seep through and are left behind when the water dries off.
Can I leave the residue? Is it harmful?
I know many people love the crusty old terracotta pots look. I agree, it can look amazing 😊 However, the buildup of salts can damage plant roots. What you could do to keep the beautiful terracotta look and protect your plants, is clean the deposits and salt marks from the inside of the pot, while leaving the beautiful outside look.
Can I clean the pot with the plant inside it?
Before applying any cleaning process, I suggest carefully remove the plant from its pot together with all the soil. After you’re done, you’ll be able to put it back in with the whole rootball intact.
I don’t recommend leaving the plant inside during the cleaning terracotta pots process as you won’t be able to clean the part that matters, the inside of the pot, and also, some of the cleaning solutions can damage the roots.
Cleaning Method 1 – Cleaning With White Vinegar
Using white vinegar is a cheap and straightforward way to clean terracotta pots. The mixture ratio is 1 part vinegar to 20 parts water. Let the pots soak in the warm water and vinegar mixture for about 30 minutes, giving this vinegar solution time to start dissolving the deposits. After 30 minutes scrub the inside, outside, and anywhere you find the white spots.
This solution is safe to be used in the dishwasher if you can fit your pots inside! Set the dishwasher to maximum heat and the strongest water spray settings.
After you’re done, regardless of whether you used the dishwasher or manual cleaning method (e.g. with dish soap or baking soda paste), wash the pot again, but this time using plain warm water. Get the vinegar out of the pot.
If you clean pots manually, beware that you don’t make the pots break.
Cleaning Method 2 – Cleaning With Bleach
Another method to clean terracotta pots is with household bleach. The mixture ratio should be 1 part bleach with 20 parts water. If your pot size is small, you can dip them in the solution for faster removal of the deposits. Otherwise, scrub the pots with this solution. After cleaning the terracotta pots, let the pots soak in clean warm water to remove the remaining bleach. Let the pot air out for a few days, so the smell of bleach is completely gone before using it.
Preventing Mineral Deposits
1) Leaching Soil
To prevent white spots on terracotta pots, leach the salts out of the soil every few weeks. Sometimes a thin white layer of the salts and minerals is visible on the soil. You can remove this top layer. Then thoroughly soak the soil, make sure all of the soil is wet. Leave it for 10-15 minutes, give the time for soluble salts to start dissolving in water. Then, place the pot in a sink or a tub and start pouring water into the soil. Let the water drain out the bottom to flush the salts. Repeat the process several times. Each following time the color of the water coming out will be lighter.
A buildup of salts can damage your plant, so it is good practice to flush the soil regularly, every couple of weeks. This method is tested and very effective.
2) Use Rain or Distilled Water
Although the ideal solution to this problem would be to remove minerals, plants needs them for growth and development. Instead, you can try decreasing salts by watering plants with distilled water or rainwater. Distilled water and rain water contain no minerals. If you have a reverse osmosis water filtering system in your home, you could also use the water treating with it for watering your plants. A reverse osmosis filter removes 70-99% of minerals from water. This is the system I’m using in my home.
Share this post with anyone else worried about how to clean terracotta pots and keep their plants healthy.