Watering with hydrogen peroxide oxygenates the roots and cures root rot.
Contested
Hydrogen peroxide won't oxygenate your roots or cure root rot. It does give off oxygen, but in soil it fizzes away in seconds, and strong enough to matter it burns roots and soil life alike. Root rot comes from waterlogged soil — fix the drainage and ease off the watering; that's what actually saves the roots.
What is actually known
Hydrogen peroxide does release oxygen as it breaks down, which is where the idea comes from — but in soil it decomposes almost instantly on contact with organic matter and microbes, so any oxygen boost to the roots is fleeting and negligible, not a lasting supply. At concentrations strong enough to do anything it is indiscriminate: it harms beneficial soil life and fine root hairs along with any pathogen. Root rot is really a drainage-and-overwatering problem — the water-mould pathogens that cause it thrive in waterlogged soil — so the fix is a free-draining mix, a working drainage hole, and watering less, not a peroxide drench.
Evidence: not yet confirmed against its 2 sources.
what this rests on - 2 pointers
hydrogen peroxide decomposes near-instantly in soil so any root oxygenation is transient and negligible
and meaningful concentrations harm soil biota and roots; root rot is a drainage/overwatering (oomycete) problem; extension consensus
When would that grow at your place? →
Cite this page
Milpa Gardens. "Watering with hydrogen peroxide oxygenates the roots and cures root rot." Evidence grade: Contested. https://milpa.garden/beliefs/hydrogen-peroxide-plants-peroxide-root-rot/
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