Updated at: 25-08-2022 - By: Sienna Lewis

If you’re reading this, you’re undoubtedly curious in thuricide’s application in the garden and how it works. Bacillus thuringienis (Bt), or more frequently thuricide, is a popular choice among gardeners for pest control. Learn more about Bt pest control by reading on.

What is Bacillus Thuringiensis?

An organism that lives in the soil is known as a Bt bacteria. Insecticides that target leaf-eating insects are particularly effective with this product. Insects will consume the thuricide, which will have an adverse effect on their stomach linings.

How to Be Safe With Bt (Bacillus thuringiensis) - FineGardening

They will starve to death if they can’t get food for hours. The most prevalent Bt strain, Kurstaki, is effective in eradicating caterpillars and other pests that feed on needles and leaves.

Crystal protein, a key component of Bt’s active ingredient, is effective against pests. This poison paralyzes the digestive system of insects, causing them to starve to death. Caterpillars such as corn borers, leaf rollers, tomato hornworms, and cabbage loopers are the primary targets of the Kurstaki strain. Mosquitoes and flies can now be killed by newer strains.

What You Need to Remember

In order to use Bt, you need to know what Bacillus thuringeinsis is, as well as other important information about the product.

Read the label carefully

If your garden doesn’t have the pests for Bt, you don’t need to use one. It’s very important to read the label. It’s important to know that thurcide products have a limited ability to kill some insects. Insecticides, like other pesticides, can become ineffective if they are overused.

It’s also important to keep in mind that thuricide only affects insects that consume it. When larvae have already entered your fruits and vegetables, spraying thuricide will have little effect. Make sure to keep an eye on your plants on a frequent basis.

How to Apply Thuricide

When it comes to antibiotics, Bacillus thuringeinsis might cause resistance if it’s overused. As a result, if you abuse thuricide, it will no longer be effective against caterpillars and other insects. Use cautious when applying thuricide to prevent it from losing its efficacy in eradicating these obnoxious pests.

There are two main kinds of thuricide: liquid and powdered. Liquid solutions are preferred by the majority of gardeners due to the greater degree of control they provide. Mix your solution according to the bottle’s instructions.

Spray the damaged area of your plant sparingly with the prepared solution. Inspect leaves for caterpillar damage and spray the mixture over them, paying particular attention to the underside and tops of leaves. Thuricide should not drip, so be sure to apply a light application.

Finally, don’t expect results right away. To witness a drop in the number of caterpillars, it could take days or weeks. You should apply the product to the affected area every 10 days or so until the issue is resolved.

Why Do You Need a Hobby Greenhouse?

Consider a hobby greenhouse if you want to safeguard your plants from pests and other elements that could harm them. If you’re still not convinced, consider these benefits of owning a small greenhouse:

It protects your plants from harmful insects

Mini greenhouses reduce the likelihood of pests being attracted to your plants. Pests such as caterpillars, aphids and other insects and animals are eager to feast on your crops and plants. A greenhouse also protects them from infections that could be harmful to them.

Get Rid of Pest Caterpillars In The Garden Once And For All! - YouTube

It’s great for gardeners without much space to work with

A hobby greenhouse is an excellent alternative if you want to get into gardening but lack the room. A six-foot-tall greenhouse is considered a small one. Smaller versions are also available, which can be used on patios, decks, and even tables if this one is too large for you. In addition, it provides the same advantages as a standard greenhouse.

You can start planting your crops earlier

A compact greenhouse allows you to plant early, even before the cold season begins in your location, thanks to the ability to manage the temperature inside. To get an early harvest, transplant your plants into the garden as soon as the weather warms up.

It keeps your plants safe from unpredictable weather

Tender plants do well in little greenhouses because they are protected from harsh weather conditions such as ice, frost, snow, and high winds. When the weather warms up, you can transplant them back into your garden from the hobby greenhouse.


If your garden is being demolished by caterpillars, you can use a naturally occurring bacteria called Bt, or Bacillus thuringiensis, to eliminate the problem. Many of the Bt types are organically certified and can be administered as a liquid or powder.

Using Bt to get rid of caterpillars in your garden is a simple process.

About Bt (Bacillus thuringiensis)

Soil contains naturally occurring microorganisms known as Bt (Bacillus thuringiensis). The bacteria create proteins that paralyze the caterpillar’s digestive tract, causing them to cease feeding and eventually die.

Because it is benign to humans, animals, and beneficial insects, Bt can be used safely in organic gardens. For use in vegetable gardens up until harvest, however all vegetables and herbs must still be carefully washed before consumption.

Certified Organic Bt

Organic certification does not apply to all commercial Bt products. Non-organic solvents are used in many liquid forms, and some products are manufactured with genetically engineered Bt (which is not permitted in organic gardens). Look for the Organic Materials Research Institute’s accreditation seal if you want organic Bt (OMRI). Powdered Bt is the most common form of certified organic Bt.

Types of Bt

Various Bt products are available, from powder to bait to liquid concentrate, and each has its own advantages and disadvantages. There are a variety of Bt strains available for various applications, including:

  • A popular variant of Bt is Bt (var. kurstaki). A variety of leaf-eating caterpillars, such as bagworms and cabbage worm larvae and tent caterpillars, as well as tobacco hornworms and European corn borer larvae, are all killed by this pesticide. Brand names like Dipel and Thuricide are widely used to market it.
  • Mosquitoes, gnats, and black flies are the primary prey of Bti (var. israelensis). Gnatrol, Bactimos, Mosquito Dunks, and Bactimos are some of the most frequent names for this product. A soil drench rather than a foliar spray is the preferred method of application for this strain.
  • Elm leaf beetle, cottonwood leaf beetle, and potato beetle are all targets of Bt (var. tenebrionis/San Diego). Among the many brand names for this product are Trident, M-One, and Novodor, to name just a few.

How to Apply Bt

It is possible to apply concentrated or wettable forms of regular Bt to the foliage of infected plants using a small spray bottle or garden sprayer. Dosage and mixing must be followed to the letter to get proper results.

Using the bacteria BT to combat caterpillars on our green leafy vegetables - YouTube

When applying Bt:

  • Bt must be thoroughly applied in order for it to be effective. It’s important to apply a uniform coating to both the top and bottom of the leaves, as they eat both. Plants don’t need to be completely submerged in water.
    • Apply Bt Carefully: Be sure to only apply the spray to the plants that are infested by caterpillars, so that you are only targeting the pests.
  • It may take a few days for Bt to start working; be patient.
  • Bt degrades quickly in the sun and only lasts a few days, so apply multiple doses. Apply as soon as you notice an infestation, and if the caterpillars return, reapply every week.
  • In order to prevent resistance to Bt from developing, use it only when absolutely essential. Use Bt as part of an integrated pest management program that includes beneficial predators and other natural controls.
  • When it comes to the shelf life of Bt goods, powdered versions survive longer than liquid ones. A cold, dry and well-ventilated area is ideal for keeping Bt fresh for the longest period of time.

Protect the Butterflies

Monarch butterfly larvae and other beneficial butterflies and moths are among the many species of caterpillars that have been eradicated by the dominant Bt strain. Insect larvae eat on certain plants, such as milkweed for the monarch butterfly. When using Bt, it is critical to ensure that only the plants that are infected get sprayed. You don’t want to spray too much or let the substance drift over to other plants that might be harboring a bug that is both harmless and attractive!