Mildew/mold starting to appear in my seed trays

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Topic by krissifitz posted 03-05-2010 08:16 AM 12482 views 0 times favorited 7 replies Add to Favorites Watch
View krissifitz's profile


4 posts in 3011 days

03-05-2010 08:16 AM

So I just planted my seeds in my mini-greenhouse/seed tray last week and I have teeny tiny sprouts coming up but I noticed a little bit of fuzzy mold starting on a few of the pods… (I planted marigolds and portulacas)

should I remove them?
Is there something I can spray to prevent this on my next set of tray?
Is there a way to fix it now that it has started?

There are little air vents on my mini greenhouse so should I open those. I’m not sure how long you are supppose to leave them covered. I will post some pictures tonite after work.

Thanks for any suggestions!

View countrygal's profile


364 posts in 3640 days

03-05-2010 09:16 AM

Your tray is too wet.You could pick off the mold if it is just a bit,not sure what you mean by pods,but keep that lid off.I hate those lids as they cause more damage than good.

-- Southwestern Ontario Canada Zone5b

View DavesYard's profile


304 posts in 2900 days
hardiness zone 5b

03-05-2010 09:44 AM

I sprinkled ground cinnamon on all of my cups with new seedlings. I read it somewhere on the net that it helps with overly wet soil, fungus, and dampening off. I don’t know why it works but it’s working for me. I’ll try to look into it a bit more.

But yeah, your soil is too wet. Try taking the lid off and blowing some heat on it to dry it out a bit. Also try bottom-watering instead of top watering if possible, so the roots can suck up the moisture but it doesnt sit at the top.

(My, ive learned a lot on this site)

View DavesYard's profile


304 posts in 2900 days
hardiness zone 5b

03-05-2010 09:48 AM


(also has the same info only condensed)

There are some other tips that can help to prevent damping off:

You can pre-soak seeds in a blend of 3% Hydrogen Peroxide and water. Some gardeners prefer to purchase 35% Hydrogen Peroxide and dilute it at home to 3%. At the proper dilution, I have found that standard 3% Hydrogen Peroxide, even though it has fixatives, doesn’t harm my seeds or seedlings. Here’s the ratio of Peroxide to water:

Seed Soak: 2 TBSP. of Hydrogen Peroxide to 2 cups or 16 ounces of boiled and cooled distilled water.

Chamomile is an excellent agent to prevent damping off:

Use three chamomile teabags. Pour boiled distilled water and steep for fifteen to twenty minutes, then add the concentrate to a sterilized gallon milk jug and top off with more boiled distilled water. Once seedlings are up and growing, use this in a sterilized spray bottle to spritz and mist seedlings.

Hydrogen Peroxide again is also useful in preventing Damping-Off Disease after the seeds have sprouted:

This time, add 1 cup of 3% Hydrogen Peroxide to a gallon of boiled distilled water. Use this to mist seedlings.

You may be surprised to learn that cinnamon has excellent anti-fungal properties and acts as a deterrent to damping-off:

Simply sprinkle the surface of the potting medium with ground cinnamon.

Once seedlings start to emerge, remove any covering and put them under grow lights. This is crucial so that seedlings can grow stout and strong and this goes a long way to preventing damping-off.
Thin seedlings. Transplant them or remove them, but prevent overcrowding. Thinning assures that the remaining seedlings will be stronger and will grow normally. It also will help to maintain good air circulation between plants.

Preventing damping-off is a simple blend of common sense, cleanliness, and good gardening practice. By using some of these helpful hints and techniques, gardeners can nip damping-off in the bud. Try a few of these tips and see if your success rate increases!

Hope this helps.

View Bon's profile


7374 posts in 3623 days
hardiness zone 5a

03-05-2010 09:51 AM

I never use lids or plastic to cover my seedlings for the same reason.I too would take the lids off.
Dave pretty soon we will be calling you “Dave the Gardener from Whitby.” (lol) Good advice.

-- Bon,Hastings, 5a....Always room for one more

View Penny's profile


318 posts in 3178 days
hardiness zone 5b

03-05-2010 10:25 AM

I’ve used cinnamon for years if that happens and it does work like a charm.

-- Gardening is Great Therapy!!.....Georgian Bay 5b

View weirdone's profile


18 posts in 2518 days
hardiness zone 5

03-18-2011 03:34 AM

Hi all by the way I”m an old farmer and jack of all trades .I just love to try to grow things .I built a grow room with heat pads grow lights etc, it’s supper insulated.I had trouble with mold , I cover things with plastic to keep things warmer. I figured i had a ventilation problem so i fixed up a computer fan with a stand it blows the air across the top of the starter trays witch at times are about 3×9 ft i don’t have any more mold i think air movement is more important than moisture. PS. Love ya all HF Wierdone

View jroot's profile


5121 posts in 3473 days
hardiness zone 5a

03-18-2011 09:15 AM

That is exactly what I think as well, Weirdone. Keep the air moving.

-- jroot ....... Southern Ontario .......... grow zone 5A ...................."Gardening is an exercise in optimism." ....... . . Author Unknown

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