Pesticides can be horrible chemicals. They can be bad for your health, and bad for the environment. Homemade pesticides, can be far less intrusive, much less harmful, and cheaper.
In this guide we will teach you, how to make homemade pesticides for killing bugs on a cannabis plant. There are many different ways, some are more effective than others, but they all do the job they are supposed to do if used correctly.
If you need help killing bugs on your cannabis plants, feel free to ask for help in our cannabis growers forum
- How Homemade Pesticides Work
- Before Treating Your Plant
- Treating Your Plants
- Making Homemade Pesticides
- Killing Bugs in The Root Zone
How Homemade Pesticides Work
You can use homemade pesticides to kill bugs on a cannabis plant, and also, prevent them. By adding certain smells to the grow room, you can deter pests from ever coming near your plants.
Plants with a strong, unpleasant smell, such as garlic, onions, or mint, can be used as a deterrent to keep all sorts of bugs and pests away.
Using peppers will add capsaicin to the pesticide. This is the chemical which makes you feel that hot spicy feeling when we eat spicy foods. This will get into the insects eyes, and make the plant uncomfortable to live on, so they will leave the plants that are treated with it.
By using a soap, you can add extra surface tension to the water. This will trap the bugs, and make it harder for them to move. They may drown in the bubbles, but will also be impacted more by the pesticide, as the soap and pesticide will emulsify.
Thing to do Before Treating Cannabis Plants With Pesticides
Safety is the number one priority at all times. Even though these are homemade pesticides, you should still take great care when using them. If you breathe them in, or get them into your eyes, it may be uncomfortable.
Wear goggles if necessary, and turn off the fans in the grow room to prevent the mist being blown back into your face.
Make sure your plants are not under light! The droplets formed by the spray can reflect the light and cause light burn. Spray your plants away from the lights, and return them to the grow room when they are dry.
This will also give you the chance to clean inside the grow room whilst the plants are drying outside of the grow room. It will also allow you to inspect the grow room, to find out how the bugs are getting in.
Find Where the Bugs are Coming From
It’s going to be a waste of time treating your plants, if you haven’t found out how bugs got into your grow room.
There are many ways for insects to get into the grow room. If you don’t find out how they’re getting into yours, the problem may not go away.
Make sure all intake vents are covered with gauze, or netting, like a pair of nylon tights or stockings. This will allow air to pass through, but will stop large bugs from being able to enter.
You also need to take care not to bring any insects into the grow room yourself! Bugs can get caught in your hair, your clothes, eggs can even get under your fingernails.
It is hard to fully prevent bugs being bought into the grow room, but by showering and changing clothes before you visit your plants can seriously reduce the risk
Clean the grow room thoroughly, and ensure there are no tears, or gaps, where bugs can squeeze in. When the grow room is properly cleaned and sealed, you can go on to treating your plants.
Test the Pesticide First!
Though these pesticides are homemade, they can still cause damage to your plants if used at too much of a high dose.
After mixing your pesticide, you should test it on a small leaf, and wait for a few hours to see if there is any damage
You will be looking for patches, or colour change in the leaf. The leaf may also start to wilt, or dry out. If there are any of these symptoms after testing, the solution is too strong, and should be diluted further. Just add more water, mix and test again.
How to Treat a Cannabis Plant With Homemade Pesticides
To make sure you get the result you want after treating your plants, you need to make sure you treat them properly. This means you can not miss a spot!
When you are spraying the leaves of your plants, spray the top, and the under side! Most bugs, will lay their eggs either in the medium, or on the underside of the leaves. If you don’t get these bits, the eggs will hatch and you would have to start all over again.
Different bugs have different life cycles, and you need to hit them at the right time. Just one treatment is not enough.
For the best results treat you plant once, every three days, three times. That means one today, one in three days, and another in six days.
Doing this should hit the pests at different times in their life cycle. It will prevent them from laying eggs, and breeding, so within a week the pests should be gone.
Spraying the Leaves of a Cannabis Plant Properly
Most cannabis plant pests, wil live on the plant itself for most of their life cycle. Some larvae and eggs will be in the medium, but most live bugs will live on, and around the plants themselves.
These pests are tiny, and very easy to miss, so for the best results, you need to cover as much of your plant as possible.
Start off by spraying the whole plant from above with a fine mist. Make your way down, and around the plant top to bottom, making sure you cover the top side of every leaf.
Next, you need to cover the under side of the leaves. This part isn’t easy, you will have to lift most leaves with one hand, and spray with the other.
You could try tilting the plant to make it easier, or even turning it upside down. Only do this if your growing in rockwool cubes, or hydroponically, other wise soil or coco will fall out of the pot onto your plants.
If the plants are small enough, you can dip them in your homemade pesticide, to effectively cover the whole plant. Of course, this will take a container that will fit your whole plant into.
Treating the Medium of a Cannabis Plant to Remove Bugs
Some insects, will lay eggs, or live in the medium, throughout some of their life cycle. Because of this, you can stop bugs emerging from the medium by using something to cover it.
Diatomaceous earth is highly recommended. But using sand, can also work. This will damage the eggs, to prevent them hatching, and will also make it harder for those insects in the medium to get out.
Be careful when spraying the medium with pesticides, as your plant may absorb it though the root zone.
Using pesticides on your medium may affect the pH and EC levels. Cover it with sand or dimatoecous earth, rather than spraying it with any of these homemade pesticides.
Making Homemade Pesticides
Homemade pesticides are a great way to treat a cannabis bug infestation, cheaply, effectively, and in an environmentally friendly way.
Rather than using harsh chemicals, you can use natural ingredients to deter bugs from coming into your grow room. They can also stop the mating cycle of the bugs on your plant, which will reduce their numbers, and in most cases, remove them completely.
Use the correct dosage, treat the plants properly, and make sure there is no easy way for bugs to get back into the grow room. This will keep your crop pest free, and make the whole grow a more enjoyable experience.
Every Cannabis grower needs to keep a bottle of neem oil in their arsenal. Neem oil is a very popular pesticide. It is non toxic to birds, plants, animals, and is broken down quickly by light and bacteria. So it is very environmentally friendly.
At the same time, neem oil is a very effective pesticide. If digested, it will have an effect on the eating pattern of an insect. Because of its smell, and its effect on bugs, it will reduce the amount the bugs eat, and also acts as a deterrent.
Neem oil will interfere with hormone systems in insects. This will stop them from mating, eating, and laying eggs, and eventually, your pest problem will be over.
How to Make Neem Oil Spray
- Take 2 ml of Castile Soap, and stir it into 1L of water
- Slowly stir 5ml of Neem oil into the mix
The neem oil will not mix with the water easily, the soap will help “emulsify” it, and help it disperse through the mix properly. Add a little at a time, and stir, DO NOT SHAKE.
- Pour Gently into a 1L Spray Bottle
Once the solution is properly mixed, pout it slowly into a 1L Spray bottle. Avoid bubbles whilst pouring, try to reduce any foam being formed.
- Spray Your Plants
Spray your plants on the top, and underside of the leaves. Use the neem oil pesticide within 8 hours after making it.
These are ingredients you will of course have to buy. They are not things you find laying around the house. If you don’t have them already, you can order them here, but they will take a few days to arrive.
There are some things you can use, that are probably in your home right now, or at least available from the supermarket for a low cost. Though neem oil is a very reliable solution to your pest problem, there are alternatives you can use if this isn’t available to you.
Using Peppers and Garlic as a Pesticide
You can use garlic and peppers as a good deterrent to bugs and animals. So it is a great natural, homemade pesticide you can use on an outdoor grow
The capsaicin in the peppers will make the plant uncomfortable to eat, and to live on, so it is not ideal food for pests. Also, the strong smell of garlic will deter pests, as they do not like the smell of it.
The hotter the pepper, the better, you can also add onion to this mix, which will also help deter pests from your crop because of the smell.
Always test the solution on a leaf and wait for an hour before treating your plant fully. If the mix is too strong, it can cause damage to the plant, always test first.
Once you know the mix is good to use, cover the whole plant, top side of the leaves and the underside.
Bugs will come out at night to eat, and if you’re growing indoors, the lights can cause burn to your leaves. Spray your plants at night time, or just as light go off for best results.
Liquid Soap as a Pesticide
If you are in urgent need of a homemade pesticide, but have no ingredients you can immediately use, soap can be a good alternative.
Though using soap will not be as effective as other methods of pest treatment, it is readily available, and if used correctly, can be an effective pesticide against many soft bodied bugs.
Avoid antibacterial soaps, and if possible, do not use scented soaps either. Though you can use standard washing up liquid in emergencies, there are horticultural soaps you can buy online that are perfect for the job.
Liquid Soap Pesticide
Use 1.5-2 ml of liquid soap
( Dish Soap, Horticultural Soap)
Stir soap slowly into 1L of water
Spray all over your plants
Using liquid soap as a pesticide will only kill the bugs on contact, so you will need to treat often.
If you’re growing outdoors, you can use your liquid soap pesticide, and then wash it off afterwards. The surface of the leaves will be slippery, and it will help wash the pests off the plant.
Epsom salts have many uses around the home, and in the garden. Using epsom salts will not only deter bugs, but they will deliver a healthy dose of magnesium to your plant.
As calcium is used in conjunction with magnesium, this can prevent calcium deficiency arising.
Epsom salts are always handy to have around the grow room, and are very cheap! Get a bag, and keep it for when you need it. It should be unscented, and 100% magnesium sulphate.
As well as spraying your plants with epsom salts, you can sprinkle some around the top of the medium. This is especially useful outdoors, as it will keep snails and slugs away from your plants. But it will also help prevent other bugs laying eggs or living in your medium.
Killing Bugs in The Root Zone of a Cannabis Plant without Pesticides
Bugs don’t just live on cannabis leaves, and stems, but they also live in the root zone.
These bugs can be harder to see, as they live under the surface of the medium, but they can still be a big problem.
There are some great pesticides you can buy, that you can pour through your medium to eradicate any insects in there.
But there are also chemical free ways you can treat bugs in the root zone of your cannabis plant.
To stop bugs being able to leave the medium, you can cover the surface with an inch or two of diatomaceous earth. This stuff is a fine powder consisting of sharp shards of stone.
Place the diatomaceous earth over the top of your medium, and make sure you keep it dry! It doesn’t work when it gets wet!
The eggs, or bugs, will be damaged by the diatomaceous earth in two ways. It will extract the moisture from the bugs, and eggs, dehydrating them, which in most cases will kill them
The other is, as live insects crawl from your medium, through the diatomaceous earth, its skin, and wings if it has any, will be shredded and torn.
You should try not to water your plants for a few days after applying the DE, so give them a good feed and watering before you apply it. Diatomaceous earth is not very effective when it is wet.
Sand can be used in place of diamatcouse earth, but it will not be as effective. Sand consists of small sharp shards, and it will shred the wings and exoskeleton of bugs in the medium as they try to climb out.
This can be a great prevention against flying bugs such as fungus gnats or white fly, as they will crawl through the medium when they reach their adult stage with wings. The sand will damage these and they can not fly anywhere, which will also stop their ability to lay more eggs on your plants!
Drying out the Medium
An easy way to get rid of bugs in your root zone, is to dehydrate them. It is not ideal, as it can affect the plant too, but sometimes it will be worth it.
Stop watering your plants, until they begin to wilt, really let the medium dry out in between waterings. It may be a lot of stress on the plant, but it will be a lot of stress on the bugs too. To make the medium inhabitable will mean that they will have to find another place to live.
It might not get rid of the problem all together but it will definitely reduce the population of the insects living in the medium.
Final Notes on Homemade Pesticides
Making your own homemade pesticides not only reduces the cost of them, but it reduces the impact on the environment too. They are effective, and reliable.
Bugs are a part of nature, and these things happen to all growers. After time, you will know what sort of IPM schedule you need to keep bugs away from your grow room for good.
Thanks for reading! You can find more information on anything related to growing in our cannabis grow guides. All of our guides are written by experienced growers, and members of our cannabis growers forum. If you have any questions, sign up. It is free, and we are always happy to help!
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