White Stuff On Terracota Pots? Mold On TerraCota Clay Pots

Have you discovered what appears to be White or Black Mold on your Terracota Clay Pots?

Your plants could be at risk if so.

In this guide you will learn:

  • How to distinguish between mold and deposits that look similar
  • What is causing the issues & Mold on your Terracotta Pots
  • How to prevent the mold from returning & Get Rid of it.

Mold on terracotta clay pots is quite common, especially when plants are kept indoors and can be overwatered easily.

To deal with mold you’ll need to establish the cause of it to begin with, follow the most suitable methods to clean up and then prevent it from re-establishing itself on your plant or pots.

Mold growing on the exterior of your clay pots can be harmful to your health as the mold spores are breathed in and agitate respiratory allergies.

If confined to the exterior of your pots then the plant is usually safe but if mold is also present in the soil, on the plant itself this can be an issue that may result in you losing the plant.

White or black mold on your clay pots is also unsightly, whilst it is unlikely to damage the pots permanently it can leave some surface staining or discolouration once cleaned so is best to prevent or deal with it swiftly upon discovering it.

What is this White Stuff /Residue On my Terracota Pots?

If you’ve discovered white patches on your plant pots chances are you’re intrigued or even concerned for what it may be, and rightly so.

Plants are after all like part of the family, you love and care for them on a regular basis, watering them and pruning here need to keep them in tip-top shape all year round

White sediment or residue can build up on your terracotta pots, especially in areas where multiple pots may be in close proximity or when stored in darker areas and you may not have noticed it straight away.

This white residue is likely to be one of two things:

  1. White mold on your terracotta clay pots
  2. Mineral deposits seeping out of your terracotta clay pots

A quick visual inspection should be enough to determine which one you have.

Simply inspect the pot and use your finger or a utensil to lightly scrape the mystery substance.

How do I distinguish Between mold and mineral deposits?

If it’s white mold then it will be soft and scrape off the pot very easily.

Should it be mineral deposits they tend to be harder and more crusty.

Mineral deposits are from the moisture content seeping out from the inside of your terra-cotta pots since they are porous and breathable.

It is a combination of fertilizers, salts and chemicals contained in tap water that crystallises as it forms patches on the exterior of your plant pots.

Signs that There is Mold Growing on your Terracota Pots

If you’re looking to establish if you have mold problems with your terracotta pots, then this section is for you.

Mold can come in various shapes, sizes, smells and colours.

Luckily there tends to only be 3 main colours that enjoy your plant’s pots, which are outlined below:

Black Mold

Searching for signs of black mold growth on your terra cotta plant pots is probably the easiest out of the bunch.

Distinctive black spots will stand out quite obviously and can only really be mistaken for soil or general dirt.

Look for a similar fluffy or fuzzy texture to accompany the black spots; if you discover this, you’ve got black mold on your clay pots.

Touching or scraping the potential mold will highlight whether it is indeed mold of the black variety. If you’re still uncertain, it’s best to air on the side of caution and clean it thoroughly using the correct protocol.

White Mold

 White fuzzy mold on terracotta pots is generally relatively easy to spot as the white contrasts against the brownish maroon shades of clay.

That being said, at first glance, you may not realize it is our undesirable guest as it can often be mistaken for white residue on terra cotta pots.

You’ll be able to see signs of white mold, on the exterior of your plant pots, either on the side or around the rim.

The residue will be crusty and hard, like limescale in the bathroom or in your kettle, whereas mold will be soft, fluffy or fuzzy looking and can be scraped easily.

What looks like white mold can sometimes be found on the soil and the plant itself.

This is not white mold but in fact a ​harmless saprophytic fungus.

Green Mold

To seek this one out, we suggest doing the same visual inspection as the others. You’ll be able to differentiate between them as green mold by its very nature is green.

Appearance-wise it tends to be similar to white mold from a texture standpoint, with a blotchy fuzziness.

If your plants are kept outdoors, chances are they may be green algae, which is not a cause for concern. If you’re not a fan of the ‘aged’ or ‘weathered’ look on your planters, it can be cleaned off quickly enough but will likely return next season.

Algae on teh terracotta pots tend to be more slime-like in appearance and darker generally than green mold, also in early stages, it will have more ‘spotting’.

How do you keep terracotta pots from turning green?

This could be one of two things; Green mold or Algae

To prevent your terracotta clay pots from changing from vibrant brownish orange to a shade of green, you should aim to keep them clean regularly

If they’re kept outside and subject to algae growth, this isn’t preventable in its entirety

However, you can move the pots, if it’s viable, from a shaded area to a location in direct sunlight and away from sources of water such as ponds or springs

In case of Light Smell Of Mold

There’s no mistaking the memorable musty and damp aroma that mold imparts. Even a slight whiff of rot should be enough for your nostrils to take note.

To establish where the moldy smell emanates from, you’ll need to do some detective work.

The first inspection should be the terracotta plants pots, looking for any obvious signs of mold.

Next up is the plant itself and the soil.

If your plants are being watered regularly, there’s a chance they might become overwatered, which can give rise to mold growing in or on the soil.

The soil may be contaminated and cause issues here if the pot itself appears clear.

Plants can be taken out, soil changed and then repotted if needed.

Most Common Causes of Mold Growth on Terracota Pots

Discovering unwanted mold colonies setting up home on your plant pots is not out of the ordinary, but it does beg the question;

Why do plant pots get moldy?

This is due to a number of factors.

1.Moisture & Temperature

Firstly the presence of moisture from watering your plants and soil will be providing an ideal breeding ground.

Mold loves moisture after all!

It also requires the right temperature, so for plants that are kept in a greenhouse or in your home, their clay pots can be more susceptible to teh growth of white mold.

2.Dark Conditions & Poor Airflow

Dark conditions will also contribute to the conditions where mold can flourish, mold doesn’t cope well in direct sunlight.

If there is little to no regular airflow where the plants are stored this only add to the ideal conditions for mold to set in.


Since plants are watered regularly the soil can become overly wet, as this extra moisture attempts to escape the soil it will disperse through the porous terracotta.

When it does so the water will take with it any contaminants and food sources that are diluted in it, this gives an ideal surface for mold spores to colonise on as the moisture continues to seep out through the terra cotta plant pot.

So when the conditions are right mold can become established and begin spreading from there.

Once it has a starting point it can quickly spread to other plant pots and areas in your home so is best to deal with it in good time.

How to Remove Mold from Terracota Pots

If you are wondering How do you get the white stuff off of terracotta pots…

Giving your plant pots a thorough clean may take care of the unsightly mold growth but won’t always tackle the problem effectively, below we will guide you through our cleaning methods to deal with it.

Plants and their rootballs can be removed from their pot during the cleaning process to make sure they don’t suffer from the methods and can easily be repotted afterwards.

You’ll need a temporary pot to house them in.

With an empty planter, you’ll also be able to assess whether there are mold issues on the inside too.

Household cleaning products, including bleach, are detrimental to your plants so must have all traces cleaned away before reinstating the plants.

​As with all cleaning it is recommended to wear suitable PPE such as gloves and goggles and to undertake the task in a safe manner.

1.Hydrogen Peroxide

You should seek out the 3% solution or dilute stronger versions accordingly.

Use a spray bottle, with a few squirts to cover the problematic areas, you should see it begin reacting and fizzing away at the mold.

Leave it to do its job for 5-10 minutes, then wipe away the residue with a clean damp cloth and wash the plant pot.

If needed reapply and use a soft scrubbing brush to help tackle the white residue.

Once you’re confident that it is sufficiently clean wash the pot using warm water and then dry fully before resuming use.

This solution isn’t harmful to your plants so is generally the preferred method amongst green-fingered enthusiasts.

2.White Vinegar 

You’ll need to dilute around 200-250ml of vinegar in a decent sized tub with water, this should be large enough to allow you to cover the affected area.

If your container only allows the submersion of half the plant pot you can focus on one side then rotate to get the other.

Soak for 15-20 minutes so the vinegar can set to work on the deposits.

After soaking take a soft scrubbing brush to the terra cotta plant pots and use it to scrub the remaining residue off.

Once satisfied you can wash down and rinse before drying, your plants’ pots will now be ready to use again.


The bleach should be diluted before use at a ratio of 1 part bleach to 20 parts clean water.

Again we can use a spray bottle to squirt the cleaning mix over the exterior, allow it a few minutes to combat the undesirable whiteness.

Work it in using a scrubbing brush and clean damp cloth to wipe away where needed.

Make sure to clean, soak in fresh water and rinse the terra cotta pot before drying it fully.

When using bleach you should allow a few days between the cleaning process and the repotting of your plants as the fumes can linger around.

4.Baking soda

First attempt to wipe, brush or scrub the main superficial mold build-up from your pots.

Next, you’ll want to create a baking soda paste, the consistency of which should enable you to easily apply to your planters but not be too runny.

Simply add water to baking soda.

introduce this mix to the affected areas and allow it to work its magic for 15-20 minutes.

After this scrub and rinse the plant pots, removing all traces of the cleaning solution.

Allow drying thoroughly before putting your plants back in.

These methods are regarded as the most effective and safest ways to deal with mold on your terracotta plant pots, whilst you may come across other techniques we cannot confirm the safety or cleaning potential of them.

Is Mold on my Clay Pots Dangerous?

In essence, mold is dangerous, not just to your plants but also to the health of you and your family.

Our four-legged friends are also susceptible to the same negative health implications.

If you have discovered mold growth on your terra cotta plant pots or the soil and plants contained within them, it should be addressed immediately.

Mold spores can become airborne and spread their way around, which, if you keep the plant indoors, can wreak havoc with other items you have.

Which can quickly spread to furniture, soft furnishings and other items close by, which offer a surface to become a breeding ground.

The presence of this unwanted invader can result in poor health for your plants, enticing other mold or fungi into the plant pot party.

Since one of the most common causes for its growth in the first place is overwatering, the ideal conditions are unknowingly being created for this to take hold.

Mold can impact your health

Especially in those who are more sensitive to its presence and people who suffer from respiratory conditions such as asthma, hayfever or generally have ill health.

Regular and prolonged exposure to mold will have an adverse effect on overall wellbeing, symptoms include:

  • Breathing difficulties and wheezing
  • Coughing
  • Sneezing and congestion
  • Headaches
  • Lethargy and fatigue

What does mold do to my plant pots?

Whilst it is unsightly and not advisable to leave it there for the above reasons the mold presence won’t necessarily damage your plant pots.

It can create staining and discolouration but won’t cause the clay to fall apart or crack.

The longer it’s left on the pot the more likely it will be to stain or discolour, also the more challenging they become to clean.

To tackle the removal and cleaning refer to your guide.

Can you pressure wash Outdoor terracotta pots?

How do you get the white stuff off of outdoor terracotta pots?

As unsightly as it can be the white stuff can be cleaned, whether it’s mold or mineral deposits.

When you’re looking to clean the terracotta pots we recommend using a spray bottle and scrubbing brush.

No doubt some of you may want to pressure wash your terracotta pots instead.

We don’t recommend doing this in general, however, there is a slight caveat.

The reasoning behind this is that the terracotta can be quite brittle and fragile, especially if the pots have been kept outdoors for a number of years.

Aiming a jet of high powered water at your plant pots will expose weaknesses and find a way to get into small cracks or fissures.

Resulting in you destroying your pots in the process of trying to clean them.

If you have access to a pressure washer that has adjustment in the nozzle ort a variety of nozzles to choose from then you might be able to use it in the cleaning or general dirt and grime from the exterior of your terracotta plant pots.

Another option would be to stand further away so the pressure is lower.

Correct safety equipment should be used if you do decide to do pressure washing.

Should the pots be having issues with mold simply spraying the outside of your pots to clean them is not going to deal with the problem effectively, they’ll require a more thorough clean.

We still advise using our methods outlined in the cleaning section.

Preventing Mold on Terracota Pots

As I’m sure you’ve heard before, ‘prevention is better than cure.’

A statement that rings true in all areas of life.

Including when it comes to mold and your beloved plants being kept in terracotta clay pots.

So how do you prevent mold from growing in or on your clay planters?

1.Keep Pots In Sunlight & Rotate Often

Keep pots in direct sunlight as much as possible, providing the plant kept in the pot are OK with sunlight

Avoid storing plants in dark areas, mold doesn’t like direct sunlight; unfortunately, not all plants do either.  Check care instructions on your plants before doing this.

2.Don’t overwater your plants.

Excess watering will cause the soil to become overly wet.  When this happens, you’re assisting mold growth rather than preventing it as the excess water will need to escape through the porous surface of the terracotta.

3.Good Ventilation

Storing your plants in areas that have good airflow is recommended in the prevention of mold growth.

Since mold flourishes in areas that are damp, humid and warm having fresh air passing through will assist in keeping these microorganisms at bay.

Having ventilation via a window or door that can be opened, or a trickle vent or air brick will be a massive help.

Also Rotate pots often if possible. This way, you’re able to keep a more vigilant eye on their condition and tackle any signs of mold at the earliest stage

4.Act Fast when you see the Mold!

Deal with any early-stage signs of mold or mildew with urgency to prevent further spread

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