--- title: "Hey planters, been dealing with this issue for MONTHS and need some…" description: "Hey planters, been dealing with this issue for MONTHS and need some external opinions for peace of mind... Most all my plants get this white buildup. My…" url: "https://getplanta.com/community/lKxUkhzRR_aIJD7o1QvtwQ/HFPoHB3hS52AIfSsYFZbzQ" community: "Pests, diseases and problems" author: "MikeNeedsMorePlants" published: "2024-08-07T17:56:30.973315Z" language: "en" image: "https://images.getplanta.com/v1/resize/-LWzBLaV5l6nRxSL_4G_JmA3jHTVbU_NyHLK_eXBVJk/SL_GxNVATZinoo1NUBHziA.webp?size=large" --- [Community](https://getplanta.com/community.md) / [Pests, diseases and problems](https://getplanta.com/community/lKxUkhzRR_aIJD7o1QvtwQ.md) # Hey planters, been dealing with this issue for MONTHS and need some… _Posted by MikeNeedsMorePlants on 2024-08-07_ Hey planters, been dealing with this issue for MONTHS and need some external opinions for peace of mind... Most all my plants get this white buildup. My assumption was mold. As you can see, the same white stuff has appeared on my evaporative humidifier wicks as well, which is concerning as I don't want to aerosolize and breathe in the mold/spores. Now I'm wondering if it's actually hard water build up. I'm doing a simple little test (picture 4) I came up with to see if I can deduce the problem. I just watered my corn plant, so I've placed three pieces of the white stuff on the top soil to see if it grows/spreads to the surrounding dirt. If yes, could be mold. If not, could be hard water crystals. Anyone else trying to differentiate between white mold vs calcium buildup? ![Attachment 1 of 4](https://images.getplanta.com/v1/resize/-LWzBLaV5l6nRxSL_4G_JmA3jHTVbU_NyHLK_eXBVJk/SL_GxNVATZinoo1NUBHziA.webp?size=large) ![Attachment 2 of 4](https://images.getplanta.com/v1/resize/-LWzBLaV5l6nRxSL_4G_JmA3jHTVbU_NyHLK_eXBVJk/-yZNyZO3TymUqoES_TSJIQ.webp?size=large) ![Attachment 3 of 4](https://images.getplanta.com/v1/resize/-LWzBLaV5l6nRxSL_4G_JmA3jHTVbU_NyHLK_eXBVJk/D6WrZ1SrT_CUCcOqQDFWiA.webp?size=large) ![Attachment 4 of 4](https://images.getplanta.com/v1/resize/-LWzBLaV5l6nRxSL_4G_JmA3jHTVbU_NyHLK_eXBVJk/jEjOcpAYRFO7VNaQbEE3bA.webp?size=large) ## 14 comments ### MikeNeedsMorePlants commented on 2024-08-07 For treatment I've been using neem oil and a fungicide. Either it doesn't work (the "mold" is resistant and keeps coming back), or it's hard water buildup which obviously isn't going to be affected by either spray ### Hort Specialist commented on 2024-08-07 The layer of mold on your plant soil is likely harmless, saprophytic fungus. All soil contains mold spores. But your plant happens to be producing the right conditions for the spores to bloom, causing a white, fluffy layer. #### MikeNeedsMorePlants replied on 2024-08-07 That's what I thought it was, but the white stuff never got fuzzy. Hence the shift to "maybe it's calcium buildup" #### Hort Specialist replied on 2024-08-07 Could be.. try using a simple acid like lemon juice or vinegar to dissolve the calcium salts ### Doll commented on 2024-08-07 I had a plant that had this but it was mold because I was able to smell it. 🖤🪴 #### MikeNeedsMorePlants replied on 2024-08-07 Oh interesting... I'll give my plants a sniff ### Ky commented on 2024-08-07 If your using tap water it could be a calcium buildup some of my plants have it too doesn’t hurt them but if you don’t want the buildup use distilled water ### Lisa commented on 2024-08-07 To add to Ky’s comment, I had this happen to my plants and humidifier when I was a new plant momma. Everything even had a white fine covering of “dust” on it when I used the humidifier. Looked like my house was dusty all the time. Then I realized that the reason for this was because of hard water in my tap water. I bought a water filter for my faucet and use filtered water only to water everything. For the humidifier, I use distilled and also water from a natural spring located in our area. No more “dust” or “mold” at all. Good luck!! 🌿 #### MikeNeedsMorePlants replied on 2024-08-07 So when I bought my humidifier I did a HUGE amount of research, and it turns out evaporative humidifiers (mine is a Levoit 6000s) are way less likely to leave that white dust because of the way the water gets filtered through the wicks and evaporates into the air. But you are right about white dust when it comes to mist and ultrasonic humidifiers :) #### Lisa replied on 2024-08-07 Really good to know for my next humidifier purchase. Ty! #### MikeNeedsMorePlants replied on 2024-08-07 I would definitely recommend! A bit pricy but worth it imo. It keeps track of the humidity in the room so it stops when the room is at a certain humidity and turns back on when the humidity lowers ### S.R commented on 2024-08-08 This looks like mineral buildup to me. #### MikeNeedsMorePlants replied on 2024-08-08 We'll see how my test goes 👀 ### YinDeezy commented on 2024-08-08 +1 for mineral build up. I only use distilled water for my humidifiers so I don’t have to worry about routine descaling when I clean them. --- _Source: the Planta community (https://getplanta.com). Reading is open to everyone. To post, comment and like, get the Planta app: https://getplanta.com/download_