Using the following to control mold but come to think of it I have had almost no damping off this year.
I have been experimenting with 3% hydrogen peroxide in the misting water. Currently using 2 teaspoons per gallon. Seems to help. May increase.
I use well water but have always thought my seedlings do not grow as well as they should. Just started using distilled water. Seem to be getting better growth rate. Looked at distillers and they use a lot of electricity. So considering reverse osmosis.
Copied the following: By maintaining a consistent level of moisture and air and by being naturally disease and weed free, coir creates a perfect environment for starting seeds and cuttings and can be used as a seed-starting medium.
The cause is already in the medium your using. That is why the boiling water suggested helps.
Nance, what medium do you use for your seedlings?
I've never dealt with dampening-off, but I've always read seed mixes with a soil component (which reduces drainage) are more likely to have/support the fungus.
I use sieved compost, coconut coir and an apparently endless sack o unsustainably mined perlite.
I've heard watering with chamomile helps, but I think the most important factors are drainage and air circulation.
I start well over 5,000 vegetable, perennial and wildling seeds a year. Most of the seed is from my own dabble into hybridizing or that I have collected. Many of which are rare. Some I may never have the opportunity again. A few I have paid more for than what you would think anyone would pay for a seed! The fruits of my efforts are also a generous part of my income. The reason that I rambled on is so that you realize that seed starting may have a whole different meaning or value to you. Many of the things I do may not be necessary for your goals. The size, purpose and expense of your propagation efforts determine the "price" your willing to pay in $'s or time to keep your babies alive.
Air circulation is a must as a preventative measure as well as for overall plant health. It is the single most cost effective and environmentally conscious thing to do as a preventive measure against disease and pest. I run my fans 24/7 for seedlings of any cultivar. The exception being when they are covered by a transparent lid at night. Larger plants all get good air circulation 27/7. Every single plant in my greenhouse and propagation area must show a little leaf movement that is appropriate for the particular plant. If not I will check air flow with a match or lighter.
A soilless medium that will dry out sufficiently (not bone dry) between watering is a good idea. Of course do not let a young seedling dry out or goodby baby. The container also plays a role in this. I take the time to slice/cut additional areas in the sides and bottoms of the container to aid in drying out and for better air to the roots for my most valuable/rare seeds. But watch very carefully so as not to dry out to much.
Good drainage is a must. Unless of course it is a plant that likes "wet feet".
Use a soiless medium for starting seeds. The seed contains all the energy it needs along with water and light to make it the first several days (dependent on the cultivar). Anything else will harbor who knows what. If you use any thing else it should be sterilized. Why use compost if you have to kill all the good stuff in it along with the bad. Save the compost for when you pot up. If your starting a cultivar that is not prone to disease and pest problems at the seedling stage this is not as important, tomatoes come to mind. But my heirloom tomatoes and just about any other seed I grow get the same treatment. My seedlings are my "babies" and it hurts me to see any of them not make it.
I have heard the same thing about Chamomile. But have not tried it.
I also use a soilless medium with mycorrihizae. But do not see any benefit at the early seedling stage. After the early seedling stage and throughout the life of the plant it is very beneficial in my opinion.
Planted my first seed this year about 30 days ago. If I did not do the things I do damping off would have killed many by now. The value in $'s would be unacceptable. I use a magnifying glass to inspect the soil and plants of my most valuable/rare seeds at least 1 time per day until they are large enough that it is no longer necessary. Any problems will be harder to deal with if you wait until you can see it with your eyes. Today was the first day I spotted what would have caused damping off in the only 2 plants that have grown from a cross I did. Needless to say, keeping these 2 plants alive is very important. I sprayed 3% hydrogen peroxide (what you can buy over the counter) on the seedlings as well as the "fuzzy white stuff" and it immediately disappeared. Then flushed with a spray of water. In my experience if nothing had been done the seedlings (at first leaf stage) would have died from damping off or related within a day or so.
So I have increased the 3% hydrogen peroxide that I use in the misting water to 1 tablespoon per gallon of distilled/purified water. I was at 2 teaspoons per gallon. This was definitely keeping the algae within acceptable amounts. But I would like to see less. I believe it was also helping prevent problems with damping off as I have always experienced an unacceptable amount of this problem. And today was the first I noticed any this year.
If you need something stronger there is a product called ZeroTol.
I would prefer not to use anything other than air movement, plant spacing, soilless medium ... and that is what I did when doing things on a smaller scale. I would like to avoid using things that come in plastic or ... but? ...
Nance ... if you are trying the hydrogen peroxide ...
The "mix" I mentioned in a previous post is an experiment I'm doing to see if I can come up with a preventive "mix" of the 3% in a gallon of water.
This should be made fresh daily or it looses its strength.
For a severe problem like in your picture ... I would use a much stronger solution/mix. Depending on the "problem" and taking the specific cultivar and growth stage into consideration I would use the 3% at up to full strength (diluted if I thought the plant could not take it). Then I may or may not flush with plain water dependent on the same things just mentioned.
Better yet ... If you are using the microgreens for human consumption vs fodder ... I recommend you look into ZeroTol. I have not had a need to talk to a rep at the company that makes it for a couple years. But when I did ... I was very pleased with the help/info they provided. I bet they have addressed your exact problem. In fact I would think that they have commercial size microgreen growers using it as a regular part of their IPM plan.