If you are treating a sick plant or one infested with insects, use a slightly stronger mixture of one tablespoon of hydrogen peroxide in eight ounces of water. Don't use hydrogen peroxide on your plants more frequently than twice each week. If you make more than you need, you can store it.
For planted seedlings: Spray with H2O2 solution of 1 part H2O2 3% to 32 parts water (eg: around 30mls per 1 litre - measuring cup recommended). For established plants: Mix 1:1 ratio of 3% H2O2 and water (eg: 1 cup of each). Bottom or top water as usual (water soil only, do not pour on leaves).
If you use a higher concentration of hydrogen peroxide on the foliage of the plant you run the risk of burning it. You could burn the roots, but since it's necessary to kill the root rot-causing bacteria, it's a risk worth taking.
It also breaks down into the soil and releases extra oxygen that helps the plant grow new, healthy roots. Before you use hydrogen peroxide on your plants, you'll need to dilute it. Mix one part of 3 percent hydrogen peroxide with two parts water in a watering can or spray bottle.
Fungus Gnats and Fungal Infections
Double-win! To do this, mix a solution with 1 part 3% hydrogen peroxide to 3 parts water. You can use this diluted mixture as a spray or as a weekly watering habit to treat your plants from those pesky gnats.
If you are treating a sick plant or one infested with insects, use a slightly stronger mixture of one tablespoon of hydrogen peroxide in eight ounces of water. Don't use hydrogen peroxide on your plants more frequently than twice each week. If you make more than you need, you can store it.
Hydrogen peroxide can help to control fungal growth and fungal infection, such as root rot, by preventing the growth of fungi. It can also help kill fungus and bacteria on plant roots.
Does Hydrogen Peroxide Hurt Plants? Almost anything in large quantities can be harmful, and using huge doses of hydrogen peroxide in the garden is no exception. When using hydrogen peroxide for plants, however, the solution is generally diluted, making it especially safe.
Apart from being more mindful of how often and how much water you give your plants and plant roots, you can also use a mixture of 3 percent hydrogen peroxide concentration mixed in 1 quart of water once a week to encourage healthy root growth in your plants' roots or treat the spread of root rot and root decay.
Treat the soil.
Use 1-2 tablespoons of hydrogen peroxide per cup of water, and mix enough to saturate the entire root ball. Mix well, then apply to the soil. Hydrogen peroxide is root safe though it can look a little scary, because it will begin to bubble up when poured in. This is normal!
Combine a 4:1 ratio of water and Hydrogen Peroxide 3% – Oxygen Plus in a spray bottle (60ml of Hydrogen Peroxide to 300ml water). Increase to 2:1 ratio if your plant can handle it. Reduce the treatment to once a week until finished. Lightly spray the leaves to ward off unwanted pests.
To disinfect, first clean any visible dirt or grime off the area with plain soap and water. Then spray surfaces with a 50/50 mix of peroxide and water. Let it sit for five minutes or longer. Rinse surfaces that touch food, like cutting boards, but let other surfaces air dry.
Mix one pint of 3% hydrogen peroxide into a gallon of water. Water the entire plant, soaking the roots thoroughly, once every week. This oxygenates the root area, promoting development during any stage of the plant's life.
After you've cut off any dead roots, we recommend soaking them in an 80:20 solution of water to hydrogen peroxide. Five minutes or so should be sufficient.
Once root rot is identified, you must determine if the plant can be saved. If the entire root system has already become mushy, it is too late to save the plant. However, if some healthy, white, firm roots exist, try to bring the plant back to good health by replanting in fresh soil with good drainage.
Use a spray bottle to soak the infected plants thoroughly. Make sure to get the undersides of the leaves, top of the soil, and around the pot itself. Spray once a week or as you see bugs appear. The hydrogen peroxide will not kill eggs, so you may need to repeat the treatment weekly to remove all the bugs.
Hydrogen peroxide, well known as an ingredient in disinfectant products, is now also approved for controlling microbial pests on crops growing indoors and outdoors, and on certain crops after harvest.
Double Up Your Protection with Isopropyl Alcohol
With the peroxide helping to keep your plants healthy and free of bacteria, you now need to prevent contamination of the tools and equipment you use to plant, trim, and water your crops.
How to Save Overwatered Plants. Luckily, many plants can be saved if you notice the issue in time. At the first sign of overwatering, grab a bag of fresh soil and a 3% hydrogen peroxide solution.
Another product that'll help prevent the spread of root rot is non-flavoured cinnamon. After having removed the dead roots, sprinkle a thin layer onto the healthy tissue before placing into a bed of new compost.
It is not possible to reverse root rot. The treatment of this disease involves removing the affected portions of the plant. Once the rotting or dying parts have been removed, they can then be repotted in fresh soil to give the remaining healthy roots a fresh start. What does root rot look like?