To make a safe hydrogen peroxide mixture, start by mixing 1 part hydrogen peroxide with 9 parts water. Next, soak the roots in the solution for 30 minutes. After 30 minutes, remove the roots from the solution and rinse them off with clean water.
Hydrogen peroxide kills root rot-causing bacteria and fungi and restores the oxygen balance in the soil which boosts your plants' growth and health. Due to its chemical similarity to water, hydrogen peroxide is one of the safest chemicals you can use in the garden to combat root rot.
First option: Remove the plant from its pot.
Gently remove all the potting medium from around the roots of your plant. Once completely exposed, either spray or pour the hydrogen peroxide solution all over the root ball. Repot the plant in a new, damp potting mixture. Let the soil dry before watering the plant again.
Cut off any diseased roots using a sterile cutting tool like a knife or scissors. You want to make sure that you're cutting off the roots that are black and mushy. 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.
Mix 2 parts water, 1 part hydrogen peroxide, soak your soil with this mixture.
Hydrogen peroxide is effective at killing 97% of bacteria, viruses, mould spores, and fungi that are causing your plant to perish. Hydrogen peroxide kills root rot-causing fungi and restores the oxygen balance in the soil which helps your plant root system recover.
Additional tips for using hydrogen peroxide in the garden
3) Test hydrogen peroxide on a small area of the plant before using it on the entire plant. 4) Stop using hydrogen peroxide if you notice any adverse effects on the plant. 5) Soak roots in hydrogen peroxide for no more than 30 minutes.
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.
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.
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?
All you need to do is set the potted plant (be sure it has drainage holes) into the bathtub, sink, or another container that's filled with a couple inches of water. After 15 to 20 minutes, the plant will have absorbed the exact amount it needs—never too little or too much.
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 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.
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.
It is perfectly safe for plants when properly diluted and used in moderation. Adding hydrogen peroxide to water promotes better growth in plants and boosts roots ability to absorb nutrients from the soil. Diluted 3% peroxide adds needed aeration to the soil of plants and helps control fungus in the soil.
Dealing with Root Rot
Prepare plants for replanting by cleaning the roots gently under running water and removing all brown, mushy roots with a sharp pair of scissors. Cut the healthy root just above the damaged area. Work quickly to replant within a few hours.
Wash the plant roots under running water to clean the soil off. Use sterilized scissors to trim away rotting roots. Prune back the foliage of your plant. It's heartbreaking but less foliage means the new smaller root system doesn't have to work as hard and will have time to grow.
Baking Soda Fungicide
Common household baking soda is a natural product used for combating plant fungus problems. Mix 1 tbsp. of baking soda with 2-1/2 tbsp. of vegetable oil in 1 gallon of tap water.
“Water more often, and give the plant the same amount of water each time,” Morganthaler advises. “Make sure to give the water time to soak down to the roots.” A soil moisture meter can help you monitor the soil's moisture—and make sure you're on the right track for your specific plant.
Depending on the circumstances and severity of over-watering your roots may need more time for recovery than others! The good news is that most plants will bounce back between 7-14 days if they're given proper care (which includes rehydration).