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[WhatsTaters]

A seedling tray of Desmanthus illinoensis germinated yesterday, but thin white mold came with it. I took the cover off the tray and set it in full sunlight today. What else should I be doing about this mold? I'm hoping the sun burns the mold out of existence.

[TBM]

I've had white mold like that show up before. Unless it starts to show signs of damaging/consuming the seedlings, I wouldn't worry. Most molds like that only eat dead materials, not living. Could be that the soil is oversaturated in water? Could also be due to high humidity? Does it have a fowl odor present? Molds which I've dealt with that are damaging have always smelled absolutely repulsive. Neem oil should kill off the mold if there are signs it's negatively affecting your seedlings.

[WhatsTaters]

It didn't have a bad smell. I'm sure the cover promoted mold growth due to high humidity. Thanks for the advice, I will just continue to monitor them.

[LIBERTYNY]

I dont personaly care for molds, Most may be harmless but others will cause problems

I would water it with a little H2O2 for piece of mind

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[GrowerAndaShower]

IME, H2O2 won't kill most molds... I messed with mushroom cultivation for awhile. It can slow some down, because it kills the spores, but the mold itself survives and will just make more spores.  let the soil surface dry out a bit, it'll slow the mold down for sure, and you may be able to transplant the seedlings a few times to isolate them away from it? I don't know if that works for plants, but when cleaning a mushroom culture we transfer to agar, let it grow a bit, transfer away from contams, and repeat until the mold doesn't show up anymore.

***THIS IS JUST A THOUGHT, I HAVEN'T DONE THIS BEFORE***
Take my theory(which is based on working with mushrooms) with a grain of salt and maybe wait for someone more experienced to chime in.
Might be able to do that with something harder for the mold to digest but that'll still hold water for the plant. Coco Coir maybe? I'd probably try switching mediums each transplant(different molds eat different types of material). Maybe Coir, then something like topsoil, and then to peat moss? I'd put H2O2 in with the mediums to prevent any spores on the plant from germinating, and see what happens. My theory is, again, based on mushroom cultivation, not botanical experience.

Might just be best to leave it alone too.

EDIT: Just noticed you've got an Oyster block as your profile pic. Lol so you should know exactly what I'm talking about.

1 Like LIBERTYNY likes this.

[modern]

Cobweb mold is pretty common and is from a lack of air exchange. H2O2 works quite well like libertyny mentioned. Using it at 3% usually doesn't harm seedlings but others recommend dilating even further with water. I use 3% without issues.