11 Mega Reasons Why Hydrogen Peroxide For Plants Is A Must

11 Mega Reasons Why Hydrogen Peroxide For Plants Is A Must

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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! If you want to get started now, you can see the brand we recommend here.

What is Hydrogen Peroxide?

hydrogen peroxide

This is a colorless, sharp-smelling chemical which looks a bit like water. It is commonly used for household uses such as 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 6% HP and the rest ordinary H20. You may have heard of it as a 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.

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How Does It 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 actually quite positive.

But when it comes to gardening, this solution on plants does so much more than just simple water. Even though this is a chemical compound, it is actually found in rain naturally. Have you ever noticed how your plants seem to react better to rainwater rather than some from the tap? By soaking your plants in hydrogen peroxide solution, it actually 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 getting the mixture right is key. You want to soak your plants, around the roots, and get rid of fungus, spores and built up mold. A general rule of thumb is to mix about one cup of HP 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. This helps them stay healthy and grow faster – we’ve explained more below.

Below, I’ve put together 11 great reasons why you should be using hydrogen peroxide for your plants right now.


Soil Aeration and Treatment of Root Rot

Good soil aeration is really important for any garden plants. Giving your soil enough space for air and nutrients to get through to the roots of your plants is the best way to see your plants flourish. 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 all squished together and tangled up then it means the soil doesn’t have enough aeration and your plant is struggling. You will also see more toxins and disease in your soil if it is poorly aerated.


Root rot is another problem that can crop up if your soil is too compact. Typically seen in plants which have been overwatered, it is the most common cause of decay around roots of plants and shrubs. Known as Phytophthora root rot, it doesn’t just affect plants in containers as bedding plants and bulbs can also suffer from this. The difficult thing with root rot is that it can sit for years in your soil even if it hasn’t had any plants put in. It is difficult to treat because of this and is exacerbated when the ground is waterlogged or very compact. The most common time gardeners will see root rot is in potato and tomato gardens.

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.

arrow-1Use a weak solution (around 3%) and mix it roughly one part chemical to two parts water.



arrow-1Carefully pour it around the roots and the base of your plant to kill off the bacteria.



Hydrogen peroxide also helps aerate your soil which should help to prevent future cases of root rot. When it is absorbed into the soil, the hydrogen peroxide breaks down and releases oxygen. These high oxygen levels will make sure your roots are healthy and strong. 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.

Disinfect Pots, Tools, Potting Benches and Greenhouses


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. If you find a plant disease in your backyard, use 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 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.

Disinfect Growing Medium


There are hundreds of different types of growing media available. Put simply, a growing medium is a solid or liquid compound which is designed to help plants grow. This 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 through 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 sort of 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.

Sanitize Seeds


Everyone knows that seeds do best if they are 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 that 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.

Accelerate Germination


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 then 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.

Boost Root Development


If your plants are looking a little limp and lifeless, then 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 on your garden every other time you go out to water your plants.

Fight Fungal Infections


One of the best uses for hydrogen peroxide is to fight 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 really heavily. And I mean really 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! This 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 in a tray of water,  though. Water them in one place and then move the container to another. Leave the watering until the plant has very 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.

Insect Repellant


While some bugs and insects are helpful for your garden (the friendly honey bee for example) there are some that are downright pests and can really 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 1% hydrogen peroxide solution is safe to use and will keep away insects and kills any eggs. It is also much safer and cheaper than some of the 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. Aphids will be deterred from sitting on the leaves of your plants with just a spritz of this solution.

Hydroponics and Aquaponics


Using HP in a hydroponic set up 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 a water with low oxygen content. As explained above, hydrogen peroxide hugely boosts the amount of oxygen in your water and this 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. 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.

Weed Killer


While a weak solution of HP will kill off bacteria and fungus and leave your plants unharmed, a stronger concentration can actually 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 right over them for 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.

Water Treatment


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. This 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.



Do not heat or Boil


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


Store in 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.


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.


keep out of 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.


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 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!

*You might also like: Aloe vera Plant – Uses, Benefits and Proper Plant Care

24 thoughts on “11 Mega Reasons Why Hydrogen Peroxide For Plants Is A Must”

    • Yes i just did it last night but now my plant is turning bright green i was also told it works like a miracle grow i hope my plants dont die there on last week of veg any suggestions im broke so any house hold remedies

    • Thank you for your helpful information. My question is about the 10% hp. Is there a water to hp ratio with 3% or do I need to purchase the 10%? About 40% of my new zoysia grass has brown grass fungus.

  1. Wonderful information about the diverse application of HP which will go a long way in helping farmers find answers to their problems. Thank you for I am farmer myself.

  2. I once saved a huge, old Rosemary plant that was dying from root rot, by using Hydrogen Peroxide mixed with water and fish fertilizer. It worked beautifully. And, I treat my seedlings (when/if the soil they’re in starts to mold. Again, works beautifully!

  3. I do like it to clean tools, pots, work areas…

    I used it to help remove sticky fruit off palms seeds.

    I started reading this article, because something peculiar happened to two of my Agave. Both were having some rot issue after winter. Anytime, something goes off like with my Agave, Aloe, Haworthia & Gasteria. I will remove every layer leaf layer until I get to a healthy part of the plant. I cut off all the roots. There is always evidence of a root cap forming. Little nubs, like potato eyes. These two both had one or two slightly elongated nubs

    After a soak in HP solution to kill any pathogens. As well as a follow-up soak in a Bacillus subtilis bacteria, an anti-fungal preventative. After both these soaks I notice, both had one of the new roots double in size. From 5 mm to 1 centimetre.

    I’m guessing from the HP, but maybe it was the HP-Bs Combo. I just repeated the process with an Agave needing to be repotted and rootless baby Aloe. Same result for the Agave. The Aloe’s root cap to small to tell. I will have to try a third time, but wait to see if anything happens after just the HP soak.

    I do caution those that bought potting mix or themselves added beneficial mycorrhizal fungi. Or want to keep other beneficial microbes found in compost, worm castings or any other living soil.
    I would think, you would then have to depend on HP to breakdown and release any nutrients in organic matter not fully composted. Mycorrhizal can also free nutirents locked away in inorganic planting medium like pumice or lava.

    I will keep HP in mind for those cuttings or plants showing pre-rot stress. Too late to add any biological and most chemical fungicides.

  4. i am impressed….i had NO idea that H2O2 was so multifunctional and beneficial……

    i have several buddies that work in chain store retail nurseries….this should be quite a feather in their
    caps for constructive coaching for customer/consumers and positive feedback/comments to and for
    their supervisors or store managers……

  5. I am an certified organic farmer , wheat, soyabeans and corn
    Question , #1 would it be beneficial to add hydrogen peroxide to a liquid fertilizer,
    #2 what ratio of peroxide- vinegar – water for a weed killer
    #3 any advantage to spray the crop post emergence
    #4 any other time that would be beneficial to the crop

  6. Would the use of Peroxide harm the monarch catapiller that feeds on only the milkweed plant.? If so what would you suggest for yellowing leaves and spindly growth? Thank you for for all your great gardening expertise!! Pazzazz

  7. Thank you for your informative blog. It was helpful for me as well as for any other farmers. I know the uses and effects of using hydrogen peroxide for plants But I was searched for the safety precautions of using it and found this. It was what I was searching for. Keep doing your great blogging.

    My Personal blog here :

  8. We just bought a full tray of various colors of Calibrachoa plants for our flowering gardens and have found many of them are being eaten by ‘something’. We haven’t lost any yet, but I had to remove one from the garden and I’m going to re-pot in a flower pot to see if I can get it to re-bloom. The plants are all in mulch, right now a small layer as we need to add more. I believe recommendations are no more than 3 inches of mulch.

    Can you tell me what is kibbling at the flowers or eating the flowers right off. I’m very concerned as if this continues, I’ll have to rip them all out and try at this time in the season to find wave petunias. We had absolutely no problems with them in the same flowering bed. Please help.

  9. Hi,

    Thank you for your wonderful information regarding HP to treat peas fungus / root rot.
    Please may I kindly enquire, you mentioned ;” As a general rule … use 1cup to 32 cups of HP solution… please may I kindly enquire which HP solution do I buy ? Or; which solution do you recommend for my yellowing pea leaves ?

    You also mentioned using a weak solution of 3% 1part HP to 2 parts water ? I’m confused as to which one to use ?

    If I buy a higher % HP food grade solution, can I water it down to 3% ? As I have a lot of bacteria in my back yard 🙁 I’m not well off – and my peas and tomatoes ( all in 12ltr pots btw ) are drying 🙁 I would love to see them pick up !

    Please help, sending you heart felt thanks Health giving wishes … and a great big thank you for all you wonderful advice 🙏xxxxc

    Yours Sincerely,


  10. It is a good article but I have a question and don’t get clear at some point. At what part I will spray the solution (leaf or root)?My gardening tree really suffer with fungus how can I remove and get better?Thanks in advance.

  11. Initiall;y seeing this is said to myself: what a load of rubbish! Well, it is partly!

    All well and good for cleaning down tools whcih have parasites and/or bad fungus.

    What about killing off the good bacteria and fungi in the garden? A good compost you should NEVER have to use hydrogen peroxide. If you do it’s a badly done compost!

  12. Initially seeing this is said to myself: what a load of rubbish! Well, it is partly!

    All well and good for cleaning down tools whcih have parasites and/or bad fungus.

    What about killing off the good bacteria and fungi in the garden? A good compost you should NEVER have to use hydrogen peroxide. If you do it’s a badly done compost!


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