11 Reasons Why Hydrogen Peroxide For Plants Is A Must - Backyard Boss
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11 Reasons Why Hydrogen Peroxide For Plants Is A Must

Is your garden looking less than perfect? Have your plants got mold growth and fungus? As a gardener, it is really frustrating to see these problems cropping up in your backyard. And it is even more frustrating when store-bought chemicals or even natural home remedies fail to help. But there is another way.

Using this clear liquid on your plants might seem unusual, but the evidence shows it is excellent for plant roots, treating fungus, getting rid of mold, and even dealing with gnats. Stop root rot in its tracks and prevent over-watering with this wonder chemical! If you’re still not convinced, we’ve put together some great reasons why you should be using hydrogen peroxide on your plants right now!

What Is Hydrogen Peroxide?

Hydrogen peroxide is a colorless, sharp-smelling chemical that looks a bit like water. It is commonly used in the household, for example, as a disinfectant, and in cleaning products. It is rare to see pure hydrogen peroxide, as it is most commonly used as a watered-down solution. It comes mixed with water, which is typically six percent hydrogen peroxide, and the rest ordinary water.

You may have heard of it as hair bleach and peroxide is what is used by hairdressers to get a bright blonde hair color. It is used for medical problems like disinfecting small cuts or wounds and even treating boils or acne. It has a myriad of uses in household cleaning, and it can even be used to kill mites and remove algae and scum from your home aquarium.

    Brio Super Hydrogen Peroxide

A bottle of food grade hydrogen peroxide.
    This bottle of food-grade hydrogen peroxide contains 16 fluid ounces of a 12 percent solution. You can dilute it to your desired concentration using tap water.

How Does Hydrogen Peroxide Work?

It is a very similar chemical composition to water, and if it was in a sealed bottle, you may even mistake it for water. And its effect on plants is quite positive. But when it comes to gardening, a must-have product is hydrogen peroxide for plants. Even though this is a chemical compound, it is found in rain naturally.

Have you ever noticed how your plants seem to react better to rainwater rather than some from the tap? Well, rain is the natural peroxide for plants! By soaking your plants in hydrogen peroxide solution, it replicates this natural substance found in raindrops, and your plants drink it up, thinking that it’s ordinary rain!

How to Use Hydrogen Peroxide

Using hydrogen peroxide for gardening is pretty simple, but figuring out how much hydrogen peroxide to mix is key. You want to soak your plants around the roots to get rid of the fungus, spores, and built-up mold. A general rule of thumb is to mix about one cup of hydrogen peroxide solution with 32 cups of water and head out into the garden in the evening.

Pour the solution into your pots or flowerbeds and leave it to soak overnight. Make sure you concentrate on the roots of your plant and avoid spraying the solution onto flowers or leaves. You can also use a stronger solution to help seeds. One ounce of it as a solution in two cups of water will give you a great solution for seeds. It helps them stay healthy and grow faster – we’ve explained more below.

Below, I’ve put together some reasons why you should be using hydrogen peroxide for plants right now.

11 Mega Reasons Why Hydrogen Peroxide For Plants Is A Must

1. Soil Aeration and Treatment of Root Rot

peroxide for plants
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Soil aeration is the constant movement of air in the soil, which results in a renewal of gases. Well-aerated soil has a sufficient amount of gas to provide for and support a plant’s metabolic processes. The importance of soil aeration lies in its control over the two life-sustaining gases present in soil, oxygen and carbon dioxide.

If your soil is too compact, oxygen and nutrients won’t get through, and your plants could die. A good way to see if your soil is too compact is to look at the roots of plants you have growing currently. If you pull out a plant and the roots look squished together and tangled up, then it means the soil doesn’t have enough aeration, and your plant is struggling.

An inadequate supply of oxygen and carbon dioxide to the roots hinders their growth, and a deficiency in the former can slow down microbial activity. When this happens, it slows down the decomposition of the organic matter whilst fostering the formation of toxic substances. Altogether, soil aeration can promote root growth and increase the photosynthetic rate and chlorophyll content, ultimately promoting plant growth and reducing the likelihood of plant death from salt stress because of poor water quality.

What is root rot?

Root rot is a disease that infects the roots of plants that grow in wet or damp soil. The disease shares similar symptoms with other plant diseases and pests, such as wilting leaves and poor growth. This decaying disease often cuts a plant’s life short, leading to its death if not corrected. The difficult thing with root rot is that it can sit for years on your soil even if it hasn’t had any plants put in. The most common time gardeners see root rot is in potato and tomato gardens.

How to identify root rot

There are two causes for root rot; over-watered soil or a fungus, with over-watered soil being the primary cause. Saturated conditions prevent roots from absorbing the oxygen they need to live. As the roots continue to be deprived of oxygen, they decay and die, spreading the rot to healthier roots, even if the water content of the soil has been fixed.

Keeping in mind the effects of saturated soils on roots, weak roots are more vulnerable to root rot through the infection of a fungus. There is a myriad of fungi naturally present in the soil. 

On a basic level, there are four major groups of soil fungus; Zygomycota, Ascomycota, Basidiomycota, and Deuteromycota, each of which has anywhere between 1,000 and 30,000 species.

does hydrogen peroxide kill fungus
Image credits: Plant pests and diseases via Creative Commons

Most fungi are good for plants. However, 8,000 varieties are a malignant kind, the most well-known being; Armillaria, Fusarium, Phytophthora, Pythium, and Rhizoctonia. 

These fungi are present in the soil but are mostly dormant until the soil becomes waterlogged. It can resuscitate the spores and cause them to attack the oxygen-deprived roots, causing them to rot and eventually die.

Symptoms of the various fungi:

  • Armillaria: Leaf drop, die-back from leaves
  • Fusarium: Yellowing and lowering of leaves and stunted appearance of the plant
  • Phytophthora: Wilting and yellowing of leaves and die-back from branches
  • Pythium: Wilting, stunted appearance, uneven plant growth, and crown rot
  • Rhizoctonia: Rusty-brown, dry and sunken lesions on stems and roots near the soil line  

The signs you have root rot in a plant can be difficult to spot as it doesn’t appear above ground until it has well and truly taken over your plant. You will see yellow leaves and some branches dying off completely. If you dig around the roots of the plant, you will see the roots are not formed well enough. The good news is it can be treated with hydrogen peroxide.

So, if you discover root rot or believe your soil is badly aerated, here is what you can do. It can and will kill off bacteria and fungus.

How hydrogen peroxide helps with root rot

Hydrogen Peroxide (H²O²) is an organic mild antiseptic that can serve many purposes. In terms of why you should use hydrogen peroxide for root rot. It comprises two atoms of hydrogen and two atoms of oxygen. It is an ideal treatment for algae, funguses, bacteria, and nematodes, which are averse to oxygen. 

The extra oxygen ensures well-aerated soil and promotes root growth, even in clay or compact soil. Remember, it has combustible and corrosive qualities, so it must be diluted and handled with care.

To use hydrogen peroxide for plants, start with a 1 teaspoon and 8-ounce cup of water solution. This solution can protect against pests and bacterial and fungal infections, which cause root rot. If you are dealing with an active bacterial or fungal infection taking over your plant, a solution of one tablespoon per 8 ounces of water can aid in treatment.

A good rule of thumb when using hydrogen peroxide for plants is to thoroughly soak your plants with the solution after every occurrence of rain. When working with highly infected plants, drench them daily for three to five days, and keep a close eye on them, exercising your judgment from time to time.

A healthy root system should be long and untangled with fuzzy white growth on the main root, which is used for soaking up water and nutrients.

2. Disinfect Pots, Tools, Potting Benches, and Greenhouses

misting your plant
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Guess what? It’s also a great disinfectant. It is already used in medical procedures and for cleaning homes due to its great antibacterial properties. But did you know you can use it to clean your gardening tools and accessories too? 

If you’ve had a disease in the garden or found plants affected by root rot or fungus, the worry that it will spread to your other plants is real. And using tools or containers that have had diseased plants in them for other, healthy plants can cause this disease to spread.

Ever found a plant disease in your backyard and wondered “does hydrogen peroxide kill fungus on tools and containers?” Well, the answer is as simple as using a hydrogen peroxide solution to disinfect everything that might have come into contact with your troubled plants. 

It is a great fungus treatment and will take any traces of the disease off your pots or potting benches. Even if you don’t have cases of diseases in your garden, you should be disinfecting your tools regularly, anyway.

To disinfect your tools, wipe them over with a wet cloth to remove the dirt and debris, then fill a bucket with a hydrogen peroxide solution. For this, you should use around a gallon of water to two cups of the chemical.

Dip in the metal parts of your tools, but be careful not to expose wooden or plastic handles to the solution for too long, as it can cause them to deteriorate. Make sure you dry your tools thoroughly after they have been cleaned, so they don’t rust.

With potting benches, surfaces, and greenhouse glass, you should mix the solution in a container and then wear rubber gloves and take a soft cloth and wet it, so it is damp.

Wipe these surfaces thoroughly with the cloth and then dry with a clean, dry cloth. For greenhouse glass, you can also use newspaper to make the glass shiny and streak-free.

3. Disinfect Growing Medium

how much hydrogen peroxide for plants
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There are hundreds of different types of growing media available. Put a growing medium is a solid or liquid compound that is designed to help plants grow.

It can be anything from a compost mix to a peat mix. Organic potting compost will have organic matter in it, which can include bone meal, worm casing, and even bat droppings!

While this is great and packed full of nutrients for your garden and containers, you do run the risk of introducing bacteria and fungus into your garden by using this type of potting mix.

An easy way to stop disease infiltrating your garden this way is by disinfecting your chosen growing medium before you use it with a hydrogen peroxide solution.

Just put your chosen soil or potting mix into a clean, disinfected container and then sprinkle over some hydrogen peroxide mixture. The same mix as you would use to pour over a plant suffering root rot.

Allow this to settle in over a week or so, watering two or three times, and then it should be ready for use in your garden or containers.

4. Sanitize Seeds

hydrogen peroxide for root rot
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Everyone knows that seeds do best if soaked in water first, but did you know that using hydrogen peroxide in your water solution will help them germinate faster? Hydrogen peroxide will also kill off any bacteria your seeds may have picked up.

So if you’re buying them from another gardener, you can make sure you get the plants you want without bringing in any unwanted diseases into your garden.

Use a 3% hydrogen peroxide solution and pour it into a small, watertight container. Leave the seeds for around four hours, and this will kill off bacteria without affecting the seeds. 

You should then rinse the seeds thoroughly in clean, fresh water and then leave them to dry on a kitchen towel or a clean tea towel.

5. Accelerate Germination

how to germinate seeds feature image
Image credits: Markus Spiske via Unsplash

Soaking seeds in hydrogen peroxide can also accelerate germination, and even just a minute or two in a weak solution can speed up how fast your seeds will sprout. Put the seeds in a sieve, or if you can, a mesh bag works best. Something that will allow water through while keeping the seeds in place.

Unlike bleach, hydrogen peroxide takes off any bacteria without damaging the seed itself. It should be a solution of one teaspoon in about a cup of water for the seed soak. You can use a much lower concentration, but the soaking process will take much longer.

You should rinse your seeds with water and begin the germinating process straight away. You can use a thin layer of wet kitchen towels or sprinkle some potting soil into a seedling tray. These trays are often made of cardboard or other absorbent material, which will keep the seeds moist until they need to sprout.

Read your seed instructions carefully and keep them at the right temperature. Warm and moist is best, and, generally, seeds thrive in a warmer climate, so think about putting them in a seed propagator or greenhouse.

6. Boost Root Development

how to germinate seeds step by step image
Image credits: Markus Spiske via Unsplash

If your plants are looking a little limp and lifeless, give them a boost with a dose of hydrogen peroxide. While you can definitely use it as a seed booster and deal with fungal growths, it is also great for helping plants at any stage of their life do better. 

The hydrogen peroxide solution can be sprayed or absorbed straight into the soil to help boost your plant’s roots. Watering plants with hydrogen peroxide solution will introduce more oxygen into your soil

This boost of oxygen gives the roots more room to take in extra nutrients and water to feed, and it will give it a kick start or help an ailing plant get back on track. 

Use about two teaspoons of 35% hydrogen peroxide to around one gallon of water, and then use it in your garden every other time you go out to water your plants.

7. Fight Fungal Infections

spray bottle around plant germination station
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An effective treatment is using hydrogen peroxide for root rot, fighting fungal growth or mold on plants. You might be concerned about using something that will kill mold and spores around your precious plants, but you don’t need to worry. This chemical mixture is brilliant at killing off fungus while also being kind to your shrubs.

If you spot the tell-tale signs that a fungus has taken hold of your plants, then mix up some hydrogen peroxide solution and water your plant heavily. And I mean heavily. You want to almost flood your plant and keep watering until the liquid pours out of the pot or the flowerbed is waterlogged. 

Don’t panic! It might sound like bad advice, but using this much “clean” water will completely rid the area, and soil around your plant, of the bacteria-carrying dirt and flush it clean.

Don’t let your plants sit on a tray of water, though. Water them in one place and then move the container to another. Leave the watering until the plant has nearly completely dried out, and you should see the fungus die off. 

So, remember; hydrogen peroxide for powdery mildew, residues, and mold is the most effective and safe.

8. Insect Repellant

spraying the garden
Image Source: Oregon State University via Creative Commons

While some bugs and insects are helpful for your garden (the friendly honeybee, for example), some are downright pests and can damage your crops. Rather than trying to kill everything that comes into your backyard, a kinder way is to just put off the pesky bugs from coming in the first place! And this awesome clear solution can do just that.

A good rule of thumb for how much hydrogen peroxide for plants would be a 1% hydrogen peroxide solution is safe to use and will keep away insects and kill any eggs. It is also much safer and cheaper than some store-bought insecticides and repellents, which can be full of toxic chemicals harmful to pets and other wildlife. 

Some of the most common (and frustrating!) garden pests can also be repelled by this wonder chemical. It will deter aphids from sitting on the leaves of your plants with just a spritz of this solution.

9. Hydroponics and Aquaponics

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Using hydrogen peroxide in a hydroponic setup is a great way to grow healthy, thriving plants. Growing plants with hydroponics mean you can see problems like a lack of nutrients as well as bacteria growth due to the warm atmosphere. The harmful bacteria present in hydroponic gardens thrive in water with low oxygen content. 

As explained above, hydrogen peroxide hugely boosts the amount of oxygen in your water and can combat the low oxygen found in warm or room temperature water.

It will kill off bacteria too, so if you find some fungus or mold spores in your hydroponic set up you can quickly combat this with the solution. With regards to how much hydrogen peroxide is for plants, you can use a 3, 5, or 8% strength solution which is bought cheaply from supermarkets or wholesalers. 

You should keep your solution in a black bottle, though, as light makes the chemical break down faster, and if it is going to be kept in the same area as your hydroponics it will be exposed to light.

10. Weed Killer

hydrogen peroxide for plants
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While a weak solution of hydrogen peroxide will kill off bacteria and fungus and leave your plants unharmed, a stronger concentration can be used as a weed killer. A 10% concentration will kill off unwanted plants if it is applied directly to them. 

Simply mix it with water in a spray bottle to target the weeds. Or you can mix the solution in a bucket and pour it right over them in a more effective way. Just be careful not to get it on or near the flowers and wanted plants in the garden. It will kill those, too.

11. Water Treatment

peroxide for plants
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It can also be used to treat the water you use instead. If you are collecting water in a tank or water butt, you can treat it with hydrogen peroxide. Or, if you’re in the middle of summer and are forced to use tap water in your garden, you can treat it with hydrogen peroxide first. Just mix some into your watering can before you take it out into the garden.

As hydrogen peroxide has strong oxidation, it will remove any harmful chemicals or pesticides found in ordinary tap water. It includes getting rid of chlorine, which is added to water at treatment plants. In hydroponic growing, you can add the solution to your water tank, and it will fill your water with more oxygen. It purifies the water and will help your plants to absorb more nutrients.

4 Hydrogen Peroxide Safety Tips

does hydrogen peroxide kill fungus
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1. Do Not Heat or Boil

While it is really a wonder chemical, it should also be handled carefully. You should never heat or boil hydrogen peroxide as it is a very unstable compound and will explode if exposed to heat.

2. Store It in a Safe Place

For this reason, make sure it is stored in a cool, dark place away from direct sunlight or another heat source. As with all garden chemicals, it should be in a tamper-proof bottle or flask.

3. Use Rubber Gloves

If you are using a higher concentration of hydrogen peroxide, as a weed killer or before you dilute it with distilled water, then make sure you wear gloves as you handle it. Rubber gloves are recommended as ordinary gardening gloves are not waterproof.

4. Keep It Out of the Reach of Children

You should also make sure it is away from pets and children. Hydrogen peroxide, while able to be used on your skin to treat wounds and cuts, should never be swallowed or ingested. It can cause you to have too much oxygen in your blood, which can lead to a myriad of issues.

If you do use it on your skin, use it sparingly as hydrogen peroxide can reduce the number of cells you have which clean and repair damaged tissue when it is absorbed through the skin.

How Will You Use Hydrogen Peroxide?

So, did you find out something new about hydrogen peroxide? It’s not just for bleaching hair or giving your home a spring clean it’s a peroxide for plants that can be used to fight off root rot, treat water, and even as an insect repellent in the garden. As a gardener, you can sometimes feel like you’re fighting against the elements to make sure your plants thrive and grow into healthy blooms or give you a bountiful crop.

With this simple chemical, you can treat so many common gardening issues and make sure your backyard is healthy and thriving. You can start using it even before the plant is growing as a seed treatment, and if you find fungus growing around the base of a tree or long-standing plant, you can quickly treat it and bring it back to life.

Comment and share below if you have any gardening tips of your own and if you’ve found this article helpful!

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