Organic Pesticides for Caterpillars – Full Guide

caterpillar pesticides

Top 3 organic pesticides for caterpillars

Garden Safe HG-93179 Neem Oil Exact Concentrate

Neem Oil is probably the best natural repellant/killer out there. It is actually a vegetable oil, made from the seeds of the Neem tree, widely used for farming/medicine. In order to apply it, mix it with water per the exact specifications on the bottle and spray it on the affected plants or where you want to prevent any infestation.

The sweet deal with Neem Oil is that it is only harmful to pests. To insects, it has a bitter taste and they will generally avoid the treated areas. It also regulates their growth, as the Azadirachtin within it will prevent their larvae from growing into adults.

It is also not dangerous to beneficial insects, such as ladybugs and bees, since they do not eat leaves/plants. Pests, however, do and are incredibly vulnerable to it. However, do not apply when temperatures rise above 100 degrees F/38 degrees C. It will stress out the plant and eventually dry it.

Natural Pyrethrin Concentrate

Yet another top-notch organic pesticide, Pyrethrin is an extract made from the chrysanthemum flower, which uses the same chemicals for its protection. The flowers are dried and crushed, either being used as-is, or made into spray pesticides.

In order to apply it properly, read the booklet it comes with for instructions on the proper quantities of substance/water to be used. Generally, whether it comes in as powder or as a concentrate, you can simply mix it with water, shake it and spray the plants.

Also, use a small spray bottle, as you will not need much. This is due to it being an incredibly potent pesticide, killing most insects on contact. It also breaks down fast, due to its all-natural composition.

Monterey LG6150 Garden Insect Spray, Insecticide & Pesticide with Spinosad Concentrate

Last, but not least, is the Monterey LG6150. Just like the aforementioned products, it is an organic pest killer. This is due to its core ingredient – Spinosad -, a natural substance created by a soil bacteria, which is toxic to insects.

So, if it is toxic to insects, how come that it is safe? Well, the same as with the other two products. It will combat whatever insect chews through the leaves of the plants. Also, it gets absorbed by the leaves really quickly and will stay for about 10+ days, with the catch that it requires sunlight. Otherwise, its absorption rate is quite slow, ranging from 30 to more than 200 days.

It also poses a low level of toxicity to people and other mammals. However, try to use eye and skin protection or not get it on yourself. Although not toxic, it can create irritation. Apply it by following the package instructions, either through a back-sprayer or a brush for dexterous application.

Before further info, here is a useful video explaining caterpillars pest control:

Plants that repel caterpillars

Natural caterpillar repellent – garlic

Garlic, due to its natural acidity, is both a potent caterpillar repellent and killer.

The stationary method

The stationary method consists of simply planting if at all possible, the garlic in proximity to the affected area. Caterpillars, like many other pests, strongly dislike garlic for its potent smell. And remember, you are not only repelling caterpillars with it but also a myriad of other pest species.

The liquid method

In a saucepot, warm some water until it begins to steam. Add some sliced garlic and maintain temperature for 15 to 20 minutes. Allow the water to cool and then remove the garlic from the water. Add a tablespoon of liquid soap to the sprayer bottle and then add water from the pan. The soap will help with adherence to the leaves. Shake it thoroughly and it is thus ready to use.

Spray on and around the plants. Also, do it early in the morning and/or in the evening, avoiding the hottest hours of the day. The concoction will damage the plants more than the pests will. Repeat this process every few weeks.

Other such plants include:

  • Peppermint
  • Sage
  • Mugwort
  • Lavender

Caterpillar predators

Luckily, caterpillars have predators, like:

  • Birds – all kinds of birds, actually. Thus, you should allow, or even encourage them to nest near your plants (building birdhouses adds a good touch). They will get rid of pests in no time
  • Yellow Jacket and Paper wasps
  • Ladybugs (link to Amazon)

Does Neem Oil kill caterpillars? (organic)

No, and yes. No, as in it does not kill them outright. However, when it gets in contact with their eggs/young, it will stop them from maturing. Or, in the case of eggs, it will stop them from hatching. It is also a most potent repellent.

Does vinegar kill caterpillars? (organic)

Yes, however, make sure to not dilute too little vinegar in too much water. It is also a wonderful repellent.

Does soapy water kill caterpillars? (non-organic)

Yes, and it does a wonderful job at that. It basically suffocates them. Dish soap, while not organic, it does not affect your plants as industrial pesticides do, other than dry them under the sun. Thus, no worries here.

Does salt kill caterpillars? (organic)

Yes. It works especially well against caterpillars, akin to the Diatomaceous Earth. A good product is the Solimo Epsom Salt. Combine it with water and some dish soap and spray the pests.

Does Diatomaceous Earth kill caterpillars? (organic)

Yes. Just like any other pests, Diatomaceous Earth will do wonders against caterpillars. It works like soapy water, by drying and suffocating them.

Does Sevin kill caterpillars? (non-organic)

Yes, it will. Sevin is yet another caterpillar killer. It is basically a nerve poison that works on them on contact and/or when it is eaten.

However, it is a good choice to use Sevin after the infestation has occurred since it might kill off more beneficial insects than it does pests. This is due to how it is toxic to most insects, and not only to pests. Also,

Homemade caterpillar repellents

Soapy water

The simplest homemade solution, which is also an incredibly potent pest killer.

Just take a sprayer bottle, add as much water as you need and combine them with a few tablespoons of dish soap. Shake it thoroughly and then spray on the leaves/caterpillars.

Soapy water is also used in most other homemade sprays, due to how it gives a raised level of adherence to the leaves.

Chilly pepper spray

Another potent homemade killer is the chilly pepper spray. Take whatever chilly peppers you have (the more potent they are, the better they work) and chop them up. For an added guarantee to kill, add a few chopped garlic cloves to the mix. Also, add a bit of vegetable oil and some dish soap to the mix. Finally, add enough water to fill a sprayer bottle with the mix.

You can either mix it in a blender or cook everything in a sauce-pan. Regardless, when let it cool and then filtrate it. Add it to the spray bottle and give it a thorough shake. Then, spray any affected areas and those around them. The spray will kill most garden variety pests without any issues.

However, you will probably need to reapply the spray every-so-often, just to make sure that they are dead.

Oil spray

In a sprayer bottle, add 2-3 tablespoons of canola oil, 1-2 tablespoons of dish soap and enough warm water as you need for spraying. Shake it thoroughly and it is ready for use. Spray the caterpillars liberally and wait. You might require to spray them again if it doesn’t kill them after the first spray.

Vinegar spray

An incredibly potent killer that works just like the soapy water spray in creation and administration. Take a sprayer bottle, fill it 1/3 with distilled white vinegar, and the rest with water. Shake it thoroughly and spray it on the affected plants. This should actually kill them on contact, due to the natural potency of the vinegar.

Diatomaceous Earth spray

Another classic in the gardening world, it is one of the best organic pesticides out there. It works by suffocating them up, just like soapy water does.

To use it properly, take a few tablespoons of it and combine them with a gallon of water. Also, you can add some dish soap n there to give it some adherence. You should also take some dry powder and sprinkle it on the ground around the affected plants. Shake it until it is dissolved and then spray the affected plants and around them. When it dries, it will suffocate any pests.

Lemon spray

Another instant killer, just like the vinegar spray.

However, this is a bit more time-consuming. For it, take a lemon and grate its rind (outer yellow shell). Boil that in enough water as to fill a spray bottle and leave it overnight. Drain it and place the liquid in the spray bottle, and then spray the plants.

How to get rid of caterpillars in my house

For indoor caterpillar removal, you should use any of the aforementioned organic solutions. They are all safe to both humans and pets, and will basically boil down to which one stinks less in the end. Although, with them being entirely organic, you shouldn’t even have a problem with this.

Remember, caterpillars, unlike other pests, require foliage, so it is easy to determine whether you have them indoors.

How to get rid of caterpillars on:

Tomato plants, basil, cabbage, herbs, broccoli, mint, kale, raspberry, and other non-pollinating plants

Since no bees or other beneficial insects deal with this selection of plants, you can use the entire array of aforementioned pesticides.

Any water-based spray does wonders if it is one of the aforementioned ones designed to kill them. So soap, lemon, Diatomaceous earth, vinegar, and oil sprays all work wonderfully. Furthermore, throw some Diatomaceous earth (powder) around said plants, since it will deter any pests that are not airborne to near said plants.

Raspberry, although it is sustained through pollination, is self-pollinating, so no bee issues here.

Trees

Same as above. However, since trees are large, thus requiring you to spray large quantities, I advise you to pick the lemon/vinegar/soap variants. Garlic/chilly sprays might irritate any birds that fly around, and you need them, as they eat pests like the caterpillars.

Same with other smelly/pungent sprays. Diatomaceous earth might be your best bet here.

Flowers

When dealing with flowers, avoid the pistil, stamen and the petals if all possible. You do not want bees to be killed by the pesticides. Fortunately, caterpillars mostly feed on leaves, so that is a good thing. Again, use any of the aforementioned methods.

However, if you are forced to spray absolutely anything, choose one of the above methods that absorb fast. Bees are way more important than they seem, so do everything to protect them.

Furthermore, you could simply hit them and let them fall in a bucket with soapy water. They will drown in no time.