What to do after using hydrogen peroxide???! Need to get new baby transplanted soon.

[Spanky]

Thanks in advance. I just watered my 14 day old seedling’s final, indoor, coco grow bag with cal mag and botanicare pro grow to charge it up for the transplant. Before I got too far, fungus gnats started flying around and landing on the coco. I have hydrogen peroxide on hand and I plan to dilute and drench to run off with it before the baby goes in. I have been using the cal mag and nutes during the seedling stage with no problems.

Questions I hope someone can answer right away:


Do I need to wait before I transplant my seedling due to residual hydrogen peroxide? How long do I need to wait?
Should I recharge the unplanted bag with cal mag and progrow again? Or, drench with clear Ph water?



I plan to pick up some need oil, but can’t go to the store this week. I will also put a light breeze on the baby once she goes into the grow space. She has been in a different room from the grow bag with the gnats. No gnats in the seedling pot.

On a related note, this is used (one grow) coco/perlite that has been idle in a basement for 2 years and it went thru 40 degree temps all winter. Regular potting soil is also stored in the basement and it has no gnats...I used it to start my vegetable seeds. Of course, I will get new coco for next time around, but I thought I could reuse coco, that it is inert. Be interested in your thoughts on this matter, but the above questions are what I need help with soon.

You guys have helped me tremendously in the past; it feels so good to know I can call on you again!

Stay safe!

[Spanky]

Sorry, make that neem oil.

[HighDesertRat]

For gnats, I just hang a couple of sticky fly strips, and sprinkle food grade diatomaceous earth on top of the soil.
the DE only works when it's dry, so replace after watering.
The DE is silica, won't hurt you or your plants.

[Spanky]

Yes, there is an excellent tutorial on gnats. There are many solutions, especially if you can get products delivered in time. I have the hydrogen peroxide in hand. Just need more info on how to use it properly. Since my plant is not in the coco yet, I want to kill the larvae that may be in the medium. The cards are useful for telling you the level of infestation once you have it. DE...food grade! may help keep gnats from producing more larvae or, prevent larvae from being laid in the first place. I am trying to eradicate larvae, already in the medium, completely, before I transplant my precious little seedling. I will be purchasing Neem oil to prevent future infestations of gnats and many other pests. Should have had some on hand, but 20/20 right?

[SoOrbudgal]

Could cook them out in an oven if your in such a hurry?

[Spanky]

So, I did more research and it turns out coco is actually as prone to gnats as soil. The peroxide can be applied and used pretty much immediately. If used properly, it will kill the gnat larvae. (If I were growing in soil, it would also kill all the beneficial organisms.) There are likely live gnats in the environment who will want to reinfect the grow medium. I am going to try using a neem spray over the soil on a regular basis to prevent that. The peroxide can be applied throughout the grow as well so I will keep that on hand. I don’t think I will bother with the yellow sticky cards. Too me, one gnat is as bad a twenty since one gnat will lead to more and more gnats if left untreated. I also have found, that a light fan on my plant works wonders and is all natural!
Thanks for reading!

[Nausetchevy]

Try Captain Jacks. I highly recommend it! Worked for us.

[Gingerbeard]

Hey Spanky I'm an old H2O2 fan from way back. I'll tell you quick that drenching any medium with HP is a partial and temporary solution to getting rid of fungus gnats. It doesn't work. It also kills lots of beneficial microorganisms. For starting seeds in towels, it's always in my water. Plenty of circulation is the best to get rid of them.

I'll not speak on DE or other deterrents because I'm strictly soil.