Damping off prevention

[ScottinAtlanta]

I had a terrible problem in 2016 with damping off, for the first time. Lost half of my seedlings, even with the second and third plantings.

What can I do this year as prevention? I plan to wash all my germination trays and covers in 10% bleach solution, and also dunk all my potting up containers in bleach solution.

What else can I do?

[Cole_Robbie]

Don't use organic fertilizer or compost in your media. If you do, then don't let the plant get cold.

Damping off is different from other diseases in that it is a result of poor conditions: cold, overly wet, and mucky, with a surplus of organic matter for the bad bacteria to colonize. Pythium bacteria are everywhere. There's no getting rid of them. All you can do is maintain an environment that fosters the good bacteria outgrowing the bad.

[Worth1]

One to two parts hydrogen peroxide to ten parts water and spray the soil frequently.
Worth

[AKmark]

I literally start a few thousand plants a year. I have learned to let the seedlings dry out between waterings to the point that they almost wilt, the media will look very dry on top.

[Heritage]

Originally Posted by AKmark

I literally start a few thousand plants a year. I have learned to let the seedlings dry out between waterings to the point that they almost wilt, the media will look very dry on top.

I agree, this is the most important factor.

[decherdt]

New unopened seed starting mix, 1-2T 3% peroxide preplant per cell, a fan for some ventilation, and cinnamon to taste I have had less luck with Jiffy mixes, gets so wet. Going with MG for 50 toms and MG Organic for 36 peppers this year.

[oakley]

I washed all my trays and pots in July after transplanting. Before i start this up-coming early Spring i'll give another rinse.
Even tried and true seed starting mixes can be a bit different every year. No good product is ever the same.
Don't start all your seeds the same day, same week. Start over a few, three week system. Rotate the trays under your light system method for various variables. (i call it 'insurance'). I have seedlings started way early, then others more for my zone...but way too late i always say...some early starts do so much better than late starts, but might do better depending on the 'wacky' Spring climate.

I start over 400+ seedlings. Room to cull weak ones. Garden room for about 125...give away healthy ones to friends. Gives me lots of variables for a possible bad starting mix or some odd attack in a tray un-known. If i plant a dozen way early in the garden i have dozens of back-ups in the barn south window. They might be a bit leggy but they always survive and catch up with some earlier plantings.

For you maybe one big word...fan. I have a small fan on 24/7 that keeps top soils on seed start trays and the baby starts dry. Bottom watering...let those baby starts dry out by checking daily. Morning and evening. Starts need water but not wet for days. Let them dry out, watch, then give a bottom soak when bone dry to the point of scary.

When the second set of leaf is true and beauty, they need more water for a few weeks.
But still need to dry out. No formula is true but eyeing and paying attention...basic love of the plant.

[MissS]

Many of us have switched to starting our seeds in Diatomaceous Earth to prevent damping off. It has been very successful too. Here is a thread on the matter

http://www.tomatoville.com/showthread.php?t=22329

Last year I used a mix of DE and a product called NoDampOff by Lee Mosser Co. and everything was great.

[Gardeneer]

Originally Posted by MissS

Many of us have switched to starting our seeds in Diatomaceous Earth to prevent damping off. It has been very successful too. Here is a thread on the matter

http://www.tomatoville.com/showthread.php?t=22329

Last year I used a mix of DE and a product called NoDampOff by Lee Mosser Co. and everything was great.

The product called Floor Dry, sold at auto part store under different brand names is DE. It is inexpensive, light weight with balanced moisture retention and drainage. I mix it with pine bark fine to make starting mix/
My other advice:
-- Avoid vermiculite and any highly moisture retentive medium.
-- Bottom water. ( keep the top surface dry )
-- As AKMark said, let the seedlings get thirsty before watering again.
__ Avoid organic matter, as Cole mentioned.
--- Run a fan, now and then , if you can.

Damping off, IMV, is a kind of rotting caused by bacterial action ; No bacteria , no rotting. Or it might be due to lack of air where the roots are.
I have experienced fungus gnat. And found out chamomile tea (pure) , cinnamon powder and mosquito dunks work to get rid of them. But the top surface must be dry all the time.

[greenthumbomaha]

Make sure your seed starting area is disinfected too. Wipe down any shelves, tables, benches, clean any nearby drapes or blinds, clean the floor. Wipe lights. Bleach any tools and use fresh disposable gloves. Professional greenhouses do this every season. Big job but they don't want to lose their entire stock to disease.

On the flip side, I attended a class where they were making soil blocks. They used soil and compost from the garden and grew out the trays in an outside climate controlled homemade greenhouse. No problems. They laughed at the bags of expensive pristine mix.

- Lisa

[ginger2778]

Gnatrol. Same ingredient as mosquito dunks, a tiny pinch is all it takes, much cheaper than the mosquito dunks.
https://www.amazon.com/Valent-Gnatro.../dp/B00286OR26

[brownrexx]

I use the sterile, soiless seed starting mix, no fan and have never had problems. I also start my seeds in my 70 degree sunroom so I think that the warmer temperature helps. Some start their seeds in a cooler area like a basement. Fungus loves cool and damp. It's ideal for them to grow.

I also set my bag of soiless mix and also my potting soil outside for about 2 days when the temperatures are below freezing. This kills any fungus gnat eggs and possibly other things too. I have had no fungus gnats since I started doing this before starting my seeds.

[MissS]

Be very careful using the Floor Dry DE. Not all DE is created equal and if you read the above thread, you will learn that the PH of different DE products varies greatly. So if you do use the Floor Dry or other products be sure to check the ph prior to using it.

[MissMoustache]

I had that problem in 2015. For 2016 I only bottom watered, sprinkled cinnamon over all my trays and watered using chamomile tea. Also take the cover off a tray as soon as you have seedlings poking up.

I start mine in our utility room because its the only place shut off from our cats. There is a dehumidifier in there for our forced air system and I have a oscillating fan going. (I've had problems with mold too but none since I started using the fan). Havent had a problem with fungus gnats yet but I have yellow sticky traps just in case.

[Worth1]

Originally Posted by MissMoustache

I had that problem in 2015. For 2016 I only bottom watered, sprinkled cinnamon over all my trays and watered using chamomile tea. Also take the cover off a tray as soon as you have seedlings poking up.

I start mine in our utility room because its the only place shut off from our cats. There is a dehumidifier in there for our forced air system and I have a oscillating fan going. (I've had problems with mold too but none since I started using the fan). Havent had a problem with fungus gnats yet but I have yellow sticky traps just in case.

Hydrogen peroxide is far cheaper than cinnamon but it will do it.
The stuff will kill yeast big time.
Found this out the hard way making cinnamon rolls.

Worth