From "Using hydrogen Peroxide" http://www.using-hydrogen-peroxide.com/index.html

The benefits of hydrogen peroxide for a garden can be useful for any kind of a garden, and any method of gardening. Peroxide is great for plants that are planted in the ground, and it’s also great for plants in containers -- it is useful in hydroponic gardens, raised beds, and greenhouses.
Similarly, peroxide for gardening applies well with all kinds of plants: a rose garden, herb garden, vegetable garden, orchard, shade trees, flower garden or lawn -- any or all of these would benefit from hydrogen peroxide.
Peroxide works by releasing oxygen. It acts as an oxygen supplement for plants. It seems to really support both good health and strong growth for plants.
Hydrogen peroxide can also help with soil fungus: it aerates the soil, and it is anti-fungal. (It is also anti-bacterial.)

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