---
title: "Can anyone explain what this is and if there’s a way to prevent it?…"
description: "Can anyone explain what this is and if there’s a way to prevent it? I’ve had my houseplants for many years but only recently switched over to using terracotta…"
url: "https://getplanta.com/community/lKxUkhzRR_aIJD7o1QvtwQ/opxKxPont8V0WKNoWg3IEH"
community: "Pests, diseases and problems"
author: "Lauravic"
published: "2026-05-29T19:44:36.022271Z"
language: "en"
image: "https://images.getplanta.com/v1/resize/kTU8vt4E-4TSwryzMNRaYSdhbXFPrxV1dzV1zgtJn8A/qfvGz3L7R7KAHf7acFRDUA.webp?size=large"
---

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# Can anyone explain what this is and if there’s a way to prevent it?…

_Posted by Lauravic on 2026-05-29_

Can anyone explain what this is and if there’s a way to prevent it? I’ve had my houseplants for many years but only recently switched over to using terracotta pots instead of plastic. I’ve been almost consistently been getting this mold-like slimy layer on the outside of the pot. I’ve tried wiping it away but it just comes back. It doesn’t seem to be affecting my plants health at all, just a cosmetic issue.

![Attachment 1 of 2](https://images.getplanta.com/v1/resize/kTU8vt4E-4TSwryzMNRaYSdhbXFPrxV1dzV1zgtJn8A/qfvGz3L7R7KAHf7acFRDUA.webp?size=large)

![Attachment 2 of 2](https://images.getplanta.com/v1/resize/kTU8vt4E-4TSwryzMNRaYSdhbXFPrxV1dzV1zgtJn8A/GX_n7XciRG63-WnXL2CCnQ.webp?size=large)

## 2 comments

### Yara commented on 2026-05-30

This happens because terracotta is porous. As water evaporates through the pot, it leaves behind minerals and salts from tap water and fertilizers, creating a white residue on the surface.

I actually used only terracotta pots when I first got into plants. They’re great for airflow and root health, but they’re quite heavy and, once the mineral buildup appears, they don’t look as aesthetic anymore. That’s one of the reasons I eventually switched to plastic pots.

It usually isn’t harmful, but if the buildup is heavy, it can be a sign of hard water or excess fertilizer. Using filtered water can help reduce it.

For cleaning, many growers recommend wiping the pot with a diluted vinegar solution and then rinsing it thoroughly with clean water.

### plantgeek commented on 2026-05-30

mineral deposits. nothing bad for your plants. i wipe mine down with hydrogen peroxide every now and again to keep them pretty.

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