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white fuzzy stuff all over tray

Posted by cprice z9 CA (My Page) on
Thu, Mar 3, 05 at 11:03

I have two germinating trays that were sterile and filled with a sterile germinating mix of peat and perlite. I have them filled with chamomile and peppermint seeds. The tray was wrapped in plastic and set under fluorescent lights 24/7 for the last 4 days. I lifted the plastic today because I saw green and noticed that both trays are covered with a white fuzzy mass I assume to be fungus?? My set up is inside a basement with a fan blowing 24/7 in the same general area. Should I assume I have damping off or some other problem and get the trays out of the basement or should I do something else? Thanks! I'm new to forcing germination indoors and under light.

Follow-Up Postings:

RE: white fuzzy stuff all over tray

White fuzzy stuff is not damping off, but it is a mould. Damping off is when the seedlings are keeled over at soil level. If you look closely the very base of the stem is black and shrivelled and the seedling is a goner.

Sterile equipment and soil is only sterile until your breath near it, or put seed in it, or water it :) Whitw mould on the surface is not the worst kind, but it may indicate that conditions are too humid. At this point, a fungicidal spray may be necessary to prevent the seedlings being overwhelmed, something like a copper ocychlorate or sulphate. Or it might be enough just to let the surface of the soil dry out a little. Leave the lid of and move the air about a bit with the fan, but don't blast the seedlings too hard or you'll kill them.

RE: white fuzzy stuff all over tray

Thank you shrubs n bulbs, I just removed the foil I placed around the light to see if I can get more air flow. I was hoping the foil would give a better field of light but it might have caused too much humidity.

RE: white fuzzy stuff all over tray

Put a little peroxide on a Q-tip & wipe away the mold.
I have seen this mentioned several times in the growing from seed forum.
I also read that you can sprinkle a little cinnamon on the mold to get rid of it

RE: white fuzzy stuff all over tray

  • Posted by GaWd z9/10 NorCal (My Page) on
    Thu, Mar 31, 05 at 14:26

Peroxide, Physan, Neem oil, any of these will work but for the most stubborn of fungi.


RE: white fuzzy stuff all over tray

In general, if you have decent air circulation and remove the plastic for an hour a day to air the flats out, that seems to prevent the fungus. This will cause them to dry out more quickly, so mist them often enough to keep the soil uniformly moist. To reduce the need for airing-out, you can punch small holes every few inches in the plastic. This is especially helpful for seeds that require cooler germination temperatures, or if you can't tend them daily.

To start out your seed-starting mix should be as damp as a wrung-out sponge; if it's soggy that causes both fungus and rot. Rather than sowing directly into trays, sow into flats (cell inserts) or small (2") pots that have drainage, and never let water pool in the trays. Once the plants germinate, remove the plastic and place plastic grids or pebbles under the flats to hold runoff from watering (the seedlings should never have "wet feet"), which also helps supply humidity. Begin fertilizing mildly when the seedlings have a few pairs of true leaves.

If your basement is dank, you may want to open a window (though not one that will expose the trays to cold drafts) or position a floor fan to bring in fresher air from upstairs.

RE: white fuzzy stuff all over tray

The white fuzzy stuff may suddenly collapse and then germination may start. This often has happened for me.

You may find the following link interesting (and links available from it):

Here is a link that might be useful: link for above

RE: white fuzzy stuff all over tray

Powered cinnamon works for me too.


RE: white fuzzy stuff all over tray

I managed to get the white fuzzy mold on the needles of my newborn Coastal Redwoods. I've decided to put them in potting soil, outside of their sandwich bag greenhouse, and sit them in front of a window. I will also clean the needles with a q-tip dipped in peroxide whenever I notice the stuff again. It affected one of the four sprouts negatively, in that it caused the needle of one to break off easily. :(

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