Mold on soil of coleus

Hello Gardening Section,

I've started a few coleus plants from seed and their soil is now covered in a white fuzzy mold with small green spores. At first, little green dots showed up (mostly on uneven points in the soil) and then the white stuff spread around them.

They were initially planted into cut up milk cartons because I had no pots for them at the time. This is where the problem started. I had washed the cartons out with liquid dishwashing detergent, but apparently that wasn't good enough. Since then, I've transplanted them to regular pots. I rinsed them down completely, removing all old soil from the roots before moving them to their new homes, but it wasn't long before the white stuff came back (the green dots/spores showed up within 1-2 days).

Any idea what this is and how I can get rid of it? It doesn't seem to be harming the plants so far, but it's horribly unsightly.


Full shot.


Close up to show the green/brown little things in the middle of the fuzziness.


Any help is much appreciated.
-Seren

wow, gnarly! hope someone can help you!!

I was going to say it is just mycorrhizae but those wierd blobs in it make me second guess that. I have seen this once before in my soil so I am curious exactly what it is.

Gnarly is right.

I have one pot with 5 plants and another with 2. I use the 2 plants to experiment on. For the past two days I've had them in direct light - this made no difference. Today, I drowned them in chamomile tea (I read somewhere that this should be a good treatment for many mold problems), making sure to drench all parts of the soil and the stems. I'll see in a few days if it comes back from that.

The good news is that it doesn't spread through the air - my weed is still mold free.


@fattiemcnuggins: Yep, the green blobs are definitely the main concern. I'm pretty sure the white stuff is just a byproduct of their presence.

If you can I would highly recommend planting them in fresh potting soil. The only time I had mold on the top of soil is when the soil was no good any more. I think after time some of the stuff in the soil starts to brake down thus causing mold. But that's just what I think the problem is. Also when sterilizing pots you use bleach and very hot water not soap.

Toolage 87 said:

If you can I would highly recommend planting them in fresh potting soil. The only time I had mold on the top of soil is when the soil was no good any more. I think after time some of the stuff in the soil starts to brake down thus causing mold. But that's just what I think the problem is. Also when sterilizing pots you use bleach and very hot water not soap.

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My first suspect was the soil as well. I'm currently trying to test it by letting it sit, well watered, in a pot with no plants and so far (3 days) there's been no trace of the mold in this pot.
I will have to transplant them again soon, but I was hoping to wait till they've become a little bigger/stronger.

I'll keep in mind to use bleach in the future. Thanks! I'm still very new at this.

Let me see if I can get someone over here who knows exactly what this is. I am surprised I stumbled on this I thought I was the only one to see it. I wouldn't do anything drastic yet.

The soil I use is Merical Grow Moisture control. You can also use seeding soil and add your own perlite into it. Also watch how long the soil stays wet for. If it stays wet for to long that will also encourage mold growth.

fattiemcnuggins said:

Let me see if I can get someone over here who knows exactly what this is. I am surprised I stumbled on this I thought I was the only one to see it. I wouldn't do anything drastic yet.

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That would be great!

I won't do anything rash. I would hate to lose any of them - one is already starting to show purple leaves

Toolage 87 said:

The soil I use is Merical Grow Moisture control. You can also use seeding soil and add your own perlite into it. Also watch how long the soil stays wet for. If it stays wet for to long that will also encourage mold growth.

Click to expand...

My soil definitely doesn't drain as well as I'd like. It's pure cheap potting soil - so pretty much all sphagnum - but I don't think that alone would cause this. For one my weed is in the same kind of soil, though a different brand, and doing fine.

The plants i had it on finished out fine.Mine was about halfway down the side of the roots but same exact thing I'm sure. I didn't notice until I pulled the root ball at the end to see how things were looking.

Well, that's comforting. Then at least I have plenty of time to find out how to get rid of it.

So my test pot with nothing but soil finally grew some mold. It's a very light, airy coating. Very different from what I have around my plants. Based on this, I'd say the soil is not the culprit.

Just thought I'd give a small update on this:
The white stuff was dense enough that it was holding in water. Almost had a cotton candy texture. I took a knife and mixed the top soil around so that the mold wasn't visible anymore. After this the soil dried out quickly on the surface and I haven't seen the green spores since. I haven't watered it either, though - they may come back when I do. But since it seems to be fairly benign, I can live with just either scraping it off or mixing it back into the soil whenever it surfaces (that is if it even follows on the next transplant - I'm still hoping it won't).

That was the worst move you can do by mixing it into the soil. You should always remove it because it will have a higher chance of coming back again. Next time just take that part of the soil off.

Maybe just an imbalance in the soil. that would make sense for mine too bc it was my first run with no-till and skipped a couple things.

Toolage 87 said:

That was the worst move you can do by mixing it into the soil. You should always remove it because it will have a higher chance of coming back again. Next time just take that part of the soil off.

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Right. I'll do that from now on. But I couldn't scrape anything off without hurting the seedlings.
For now, I'll water from the bottom and make sure the top layer of soil doesn't get drenched.

fattiemcnuggins said:

Maybe just an imbalance in the soil. that would make sense for mine too bc it was my first run with no-till and skipped a couple things.

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Could be.

may i ask why you would let it get that bad? take em out re pot. new soil.

sunni said:

may i ask why you would let it get that bad? take em out re pot. new soil.

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Because he didn't want to damage the seedlings or put them into shock.

sunni said:

may i ask why you would let it get that bad? take em out re pot. new soil.

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As Toolage said, I didn't want to damage anything and the seedlings didn't seem to suffer from it. I think it's quite benign, but I'm still planning to kill it if I can. Dry top soil keeps it at bay. I may try to mist with hydrogen peroxide if I can get my hands on some.

oh another thing it could be is that it could be dampoff