H2O2 for extra oxygen to roots in soil-less medium


Hi people I’m thinking about starting to experiment with a dilute solution of H2O2 3% (10 vol) in chlorine-free tap water and using this solution for watering plants. I’ve read about using a ratio of 1 pint (473 mL) 3% H2O2 solution per gal (3,79 L) of water, and with this solution plants are watered once a week.
I intend to do this to deliver more oxygen to roots while using coco coir and perlite and thus growing stronger roots at any stage of plant development. I’ve read about excellent results in garden soil. This whole idea thrills me.
Does anyone have ever done this and might share his/her experiences please?


@gabarram I would only use the hydrogen peroxide if you had a issue with root rot or otherwise. This also does kill all beneficial bacteria in your growing medium. I’m not saying it won’t work, it depends on your style of growing. I have limited experience with this, and I would let others chime in for a another perspective.
@Countryboyjvd1971 @dbrn32 @Myfriendis410 @WillyJ


Nothing on my end. Generally something like coco and perlite mixture is already going to be a lot more airy than a standard soil grow. I would think a mixture like that along with smart pot or plenty holes in plastic pot would be plenty. But never tried otherwise.


Thank you @Covertgrower and @dbrn32 for your opinions. I think the danger lies in the concentration of the solution on every purpose for it. I’ve done some calculations and found that with the proportions I’d use to boost root development, the concentration of the H2O2 solution is as low as 0.33% H2O2 while as a disinfectant the concentration rises up to 6-9% or 10% to kill weeds.
Besides, I also thought of experimenting on one plant to see the reactions before going on to a bigger scale, I’d not water all the plants at once.
However, I’d treat this substance with great care and respect because it’s a powerful oxidant and I wouldn’t like to get even one plant burnt.


From the research I’ve done, you can water with it at the same ratio as for germinating seeds. 30:1
I have 100% success rate with it on seed germination the last 3 grows. I don’t water with it, but I did a lot of research on it and it does aerate the soil @gabarram


This is a time to call… @garrigan65. He will know the answer.

Hydrogen Peroxide at every watering to increase O values. Any validity to doing this?


Many thanks for encouragement. Do you use 1mL 3% H2O2 in 30 mL water, for the record?


I completely agree. Next grow I’ll switch to fabric pots, already ordered a few. Coco and perlite I’m already using, I switched to soil less medium.
But I want some more O2!


I don’t see potential danger with these very dilute solutions but at first I’d try once a week.


I would only be worried about damaging the root ecology with disinfectant which is what it is. Using it prophylacticly might cause other problems. I just don’t know.


It depends on the concentration of the H2O2 solution, to kill mold or fungus and bacteria in roots, it seems a higher concentration needed.


See that’s what the rest of us are thinking. Lots of the bacteria in root zone is actually helpful to plants. So you would be most likely killing that as well.


Yes @gabarram, I use 1ml of H2O2 to 30ml of 6.5 pH water for seed germination. I don’t use H2O2 for watering because I use 1 inch of clay pellets in the bottom of my smart pots to give the roots plenty of aeration and it works good for me.


Perhaps some scientific evidence shows the treatment is beneficial… I found two papers:

  1. Improving Soil Oxygenation with Hydrogen Peroxide Injection into Heavy Clay Loam Soil: Effect on Plant Water Status, CO2 Assimilation and Biomass of Avocado Trees (P.M. Gil, R. Ferreyra, C. Barrera, C. Zúñiga, L.A. Gurovich; ISHS Acta Horticulturae 889: VI International Symposium on Irrigation of Horticultural Crops; DOI:10.17660/ActaHortic.2011.889.71)
    The conclusions: Injecting H2O2 into a soil with low air content through the irrigation system
    significantly increased the biomass of the aerial portions of the plant, but had no
    significant effect on measured CO2 assimilation, transpiration, stomatal conductance or
    stem water potential. The increased biomass of the aerial portions of plants in treated soil
    indicates that soil H2O2 injection may have potential as a method for improving soil
    oxygen content in a heavy clay loam soil. However, the present study was conducted with
    trees in containers, and therefore, before this method is used to mitigate damage caused
    by low soil aeration in avocado orchards, further studies are needed to evaluate the
    practical and economical feasibility of using hydrogen peroxide on a larger scale in
  2. Aerated subsurface irrigation water gives growth and yield benefits to zucchini, vegetable soybean and cotton in heavy clay soils (S P BHATTARAI, S HUBER and DAVID J MIDMORE; Ann. appl. Biol. (2004), 144:285-298)
    Hydrogen peroxide (HP) at the rate of 5 litre ha-1 at the end of each irrigation cycle was injected
    through SDI tape to a field-grown zucchini (courgette) crop (Cucurbita pepo) on a saturated heavy
    clay soil in Queensland, Australia. Fruit yield, number and shoot weight increased by 25%, 29% and
    24% respectively due to HP treatment compared to the control.

The solution used for irrigation is H2O2 (50% v/v) was mixed in the irrigation water at the rate of 1 ml/L.


This morning I bought a bottle of H2O2 3% and diluted to 5 mLH2O2/250 mL tap water and adjusted pH to 6.5. I watered on the root zone two plants in coco/perlite and two plants in soil, all in vegetative stage. Many other plants are the control group. I’m going to water once a week with this solution and inspect visually the results.
Thank you all for the opinions,


Coco and perlite offer great oxygen exchanges. The sources you listed are for suffocating loam and clay soils. If you add hydrogen peroxide to coco or perlite I don’t think you’ll see any additional benefits, as they already have lots of oxygen in it. Just my two cents, doesn’t mean I’m wrong. Just a thought. @gabarram


The soil of the plants in soil is clayish and indeed coco/perlite seems to offer advantage over soil for oxigenation, but since I’m not doing hydroponics I just look for ways to get better results and I’m very concerned with proper oxigenation of the substrate.
Additionally I’m using plastic pots which I don’t like but these are what I have… Next time as I stated above I’ll swtich to fabric pots, and keep on with coco/perlite. I really don’t know if this is going to make any (at least noticeable) difference but I think it’s worth trying.


Coco is designed so you can’t over water. It retains 30% oxygen once watered due to being coco fiber and expanding like a sponge when watered. Coco is an inert media too and has no nutrients in it. You have to feed the plants as soon as the cotylydons yellow up and die. If you are just giving the plant water, she will be hungry and if you are using H2O2 you are killing off any nutrients you have in your tap water too. Also, coco should be ph of 5.5-6 with 5.8 being the sweet spot most of the time. I think this would work better in soil that is compact and you’re still feeding throughout the week and using H2O2 once a week to help oxygen get to the roots. @garrigan65 will have a better answer for you, but that’s my 2 cents


I think that’s where maybe we’re seeing things differently. Coco/perlite is not clay or anything like it. Which is where we started right?

Even standard potting soil is quite a bit different than anything clay based. Personally, they’re your plants, you can do whatever you’d like to them right? Nothing there has convinced me to add peroxide to anything I’m doing without just cause like battling root rot or something.

When I see stuff like this that I’m considering, I like to research from the opposite perspective and see how that turns out. If your rate is consistent with killing bacteria and living soil cultures, perhaps you should research effects of beneficial bacteria and microbes in soil. And see if that’s worth giving up to follow this path.


You mean air, I guess
I use Flower Power fertilizers once a week to feed the plants. Every two days I water with pH’d water alone and once in a while I add some Ca-Mg-Fe supplement. Also for prevention I add a Clean Drip to pH’d water. I can assure you I’m not giving just plain water to the plants in coco/perlite because it’s inert as you said. So far I’m not having issues with this schedule and the plants are doing fine. I’ve been thinking about delivering more oxygen to the roots in addition to the oxygen in the air trapped in the substrate.