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Help! My seedlings keep falling over dead!

Posted by FLOWPOW2 Zone 7-8 bc. ca (My Page) on
Wed, Dec 22, 04 at 13:27

Can anyone tell me why my seedling keep falling over dead? I have a plant room I keep at 15c / 60f with three, four foot flourescent double tubes.The seeds start nicely then fall over at three inches. I start them in Rubbermaid tubs with glass on top and heating pads under. I`ve tried adjusting the heat and moisture but still no luck.I`ve lowered the lights but still no good.What am I doing wrong? I`m using Sunshine #1 pot mix. Thanks, FLOW.

Follow-Up Postings:

RE: Help! My seedlings keep falling over dead!

Sounds like a textbook case of damping off. What arrangements have you made for ventilation? Do you keep the glass on after the seeds have germinated? You do need ventilation and you should remove the glass after a good number - not necessarilly all - of the seeds have germinated, long, long before they get to be 3" tall. The humidity should not be too high and you should not keep the soil or seedlings too warm - both will encourage growth of the fungus responsible for "damping off disease." The spores are pretty much ubiquitous so don't bother thinking about killing them all off, you just want to discourage too active growth of them.

So... get rid of the potting soil you've been using so far. Clean out the containers with bleach solution (they do have drainage holes, BTW, right?) and start again, with a fan not too far off but not blowing right on the seedlings, remove the glass shortly after they start to germinate, don't keep the soil any warmer than about 70F unless you're starting tropical seedlings and back it off a bit even from that once they've germinated and you'll probably find you get dramatically better results.

RE: Help! My seedlings keep falling over dead!

I'm not sure what's in your potting mix. Try switching to one specifically designed for seed starting - it will be a sterile, soilless mix. As soon as I switched, my damping off problems stopped. The above advice about ventilation is also very important.

RE: Help! My seedlings keep falling over dead!


"I`ve lowered the lights but still no good.What am I doing wrong? I`m using Sunshine #1 pot mix."

As others have suggested, the Sunshine pot mix is probably not the best thing for seed starting. I am curious about those Rubbermaid tubs. What provisions have you made for drainage? Have you made holes in the bottom of the Rubbermaid tubs? You are the first I have heard who was using them. I have been using standard black plastic seed starting trays. A bit flimsy, but widely used.

As others have suggested, clean all of your stuff with dilute Chlorox. You probably do have an infection of damping off. Definitely don't reuse any starting medium.

I use overdriven fluorescent lights for extra brightness. Check elsewhere in this forum for info about overdriving fluorescents. How long is the timer set for on your lights? Blowing your seedlings gently with an electric fan is also a good idea.

Have you had your water tested? Some water is loaded with stuff that is not good for plants, and it can accumulate to toxic levels. Where possible, I use rain water and snow water to avoid using our tap water.


RE: Help! My seedlings keep falling over dead!

As soon as you get your true leave start drying them out more.

RE: Help! My seedlings keep falling over dead!

I've heard that a thin layer of sand or grit on the soil can help against damping off, and I once tried very broken down pine duff, which seemed to have beneficial microbes to stop the bad ones.


RE: Help! My seedlings keep falling over dead!

Less watering, plenty of air movement, cleansing trays, pots, etc with a bleach solution and I find wetting the sterile seed starting medium and watering the plants thru the first few waterings after transplanting with a solution of 8 oz hydrogen peroxide (the already diluted kind you buy in the drug store, not the pure stuff that will burn your skin) per gal of water helps prevent damping off.
I, too wonder about the rubbermaid containers. I use the aluminum throw away loaf pans with mumerous holes poked in the bottom for storage. You can view at link below.

Here is a link that might be useful: Seedlings, etc.

RE: Help! My seedlings keep falling over dead!

I use a mix of peat moss and pearlite. I always sterilize it. I put it in a dish pan and pour boiling water over it till it is kinda soupy. I allow it to cool off over night then let it drain through pots or a colander. I don't plant in it till the next day. I do this even if is a new bag of peat. I only sterilize what I need for 1 or 2 days of planting each time. I do not fertilize till the plant has it's first true sets of leaves. Use only half of the fertilizer that it says on the bag .

RE: Help! My seedlings keep falling over dead!

Watering your seedlings with Chamomile tea will help prevent damping off.
You also need to do all the things everyone else mentioned. I keep fans blowing over my g-house plants 24/7 as do most commercial growers. It's cheap insurance.
You'll be amazed how trouble free your seedlings will be when you follow all the advice you have received.
This sounds like a classic case of a common problem.


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