My seed start pots in my greenhouse.....the soil (seeds not yet sorouted) has a layer of white growth like mold or fungus...looks like cotton candy almost.
I have been using a antifungal spray and will be putting a dehumidifier in there....but when it rains hard it drips in thru the seems and is damp inside.
Any tips to kill this stuff before my seeds sprout?
I would take off that top layer of mold if you can, without disturbing the seeds, then put a light layer of finely ground sphagnum moss on top or a sprinkling of the lightest Seed Starting Mix you can find.
What did you use for a seed starting medium in the first place? My guess is that you used a mix that is too heavy and holds too much water, resulting in the mold forming. Also - were your starting pots/flats perfectly CLEAN? As in, did you rinse them all in a water and light bleach solution before you used them, or did ya just grab them out of the stack and plant away? With your uber-moist growing conditions, cleanliness IS next to godliness! ;)
If you need to start over, clean pots and Seed Starting Mix is what’s needed - it’s light and already has the sphagnum as an ingredient which helps fight the moldies. ;)