Hydrogen Peroxide—Wonder Drug for Ailing Plants!
Hydrogen Peroxide—a Common Household Compound—is a Wonder Drug in the Garden!
Hydrogen peroxide, H2O2, can disinfect surfaces, whiten teeth, and is even claimed by some to possess magical medicinal properties. And while many alleged uses are completely bogus, one fantastic use for garden-variety hydrogen peroxide is actually in your garden!
Hydrogen peroxide can protect your garden plants from pests and mold, and can even supercharge plant growth from planting through harvest. When applied in the right concentration and at the right time, H2O2 can rescue sick and dying plants and restore them to full health, just like a real wonder drug!
The secret ingredient is the compound's "extra" oxygen molecule. Water, if you'll recall, is H2O (two hydrogen molecules bound to a single oxygen molecule), while hydrogen peroxide is H2O2 (two of each). When sprayed into the environment the compound decomposes into water and oxygen, and can be thought of as "water with an extra oxygen molecule."
Aside from sunlight and heat, plants need oxygen and water to grow, and because hydrogen peroxide is "oxygenated water," your plants will love it. The compound provides extra oxygen to the soil (obvious benefits), and can stop potential plant-killing "anaerobic processes" in the soil (it actually kills most/all bacteria and fungi in the soil, so don't use it routinely, only when it's necessary).
Properly diluted, hydrogen peroxide is non-toxic and EPA-approved for application in the environment.
Two Main Applications, Two Important Dilutions
Both main garden applications start with the same "3% solution of hydrogen peroxide," which is by far the most common dilution of H2O2 available from pharmacies and grocery stores everywhere. Essentially, a bottle of 3% hydrogen peroxide solution contains 3% H2O2 and 97% water (H2O). This is what you want for rescuing plants in your garden.
Other dilutions are available, but not recommended. "Forty volume fixer," for example, available from beauty supply shops, is actually 12% hydrogen peroxide. In that dilution it bleaches hair! Industrial applications can use 90% hydrogen peroxide, but in that dilution, H2O2 is too corrosive to use around the house.
For Leaves: To make a protective, revitalizing spray that we can apply to the leaves of almost any ailing garden plant (especially tomatoes), mix 4 teaspoons of 3% hydrogen peroxide with 1 quart (1 liter) of water.
For Roots: To make a soil oxygenating, plant-rescuing mixture that should only be applied to the soil—and never the leaves—mix equal amounts of 3% hydrogen peroxide and water in a 1:1 ratio. That's 1 quart of 3% H2O2 mixed with 1 quart of water (etc).
Use it Like Medicine
If your garden plants are healthy and are not stunted, suffering, or infested, do not use hydrogen peroxide—period! Think of H2O2 as "garden medicine." If your plants are flourishing they don't need H2O2, or any other medicine, to keep them healthy.
But if your soil isn't perfect, lacks oxygen, has pests, contains poorly decomposed compost or fertilizer (which can lead to anerobic toxins), etc, mix up a batch of 1:1 and water only the soil around the plants but not the leaves (which will burn from the 1:1 mixture). Repeat weekly, only as necessary! Once your ailing plants are back in action, do not add more H2O2.
The same goes for the leaf spray. If the leaves of your garden plants are healthy, happy and not suffering, do not spray them with hydrogen peroxide. If they do need help, however, mix up a batch of leaf spray H2O2 solution and liberally spray the leaves of any plant that needs help. Continue every 2-3 days as necessary. When the leaves and the plant itself are healthy, not infested, and looking good, stop spraying them with H2O2.
Hydrogen peroxide comes in a brown, opaque bottle because it's sensitive to light, so don't transfer it to a clear container, as it will fizzle out in a couple of days, becoming H2O (water), which costs a lot less right from your faucet!
Buy small, fresh bottles of hydrogen peroxide and only open/unseal them when it's time to mix and apply H2O2 to your plants. Once exposed to air, hydrogen peroxide decomposes into water and oxygen rather quickly.
To test your opened bottle of 3% hydrogen peroxide, apply a small amount to a freshly sliced potato. If the H2O2 energetically fizzes and foams, it's still good. If the fizzing is weak or nonexistent, dispose of the bottle and use a fresh one to rescue your garden.