---
product_id: 4355848
title: "Caterpillar Killer II with B.T. Concentrate"
brand: "safer"
price: "296 kr"
currency: DKK
in_stock: true
reviews_count: 8
category: "Safer"
url: https://www.desertcart.dk/products/4355848-caterpillar-killer-ii-with-b-t-concentrate
store_origin: DK
region: Denmark
---

# Safe to use up to day of harvest OMRI Listed for organic gardening 98.35% Bt Kurstaki active ingredient Caterpillar Killer II with B.T. Concentrate

**Brand:** safer
**Price:** 296 kr
**Availability:** ✅ In Stock

## Summary

> 🌱 Defend your garden organically—because perfect harvests don’t wait!

## Quick Answers

- **What is this?** Caterpillar Killer II with B.T. Concentrate by safer
- **How much does it cost?** 296 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/4355848-caterpillar-killer-ii-with-b-t-concentrate)

## Best For

- safer enthusiasts

## Why This Product

- Trusted safer brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Harvest-Ready Safety:** Use confidently up to the day of harvest—no waiting, no compromise.
- • **Sun-Smart Application:** Best applied late afternoon or cloudy days to maximize Bt effectiveness and minimize breakdown.
- • **Organic & Eco-Friendly:** OMRI Listed formula protects your garden without harming beneficial insects or the environment.
- • **Precision Pest Control:** Targets caterpillars, gypsy moth larvae, and tomato hornworms with surgical accuracy.
- • **Long-Lasting Concentrate:** 16 fl oz bottle covers extensive garden rows, delivering powerful protection season-long.

## Overview

Safer Brand Caterpillar Killer II Concentrate is a potent, OMRI Listed organic insecticide containing 98.35% Bacillus Thuringiensis var. Kurstaki. It effectively eliminates caterpillars, gypsy moth larvae, and tomato hornworms without harming beneficial insects or the environment. Safe for use up to the day of harvest, this 16 fl oz liquid concentrate offers professional-grade pest control tailored for organic gardeners seeking reliable, eco-conscious protection.

## Description

Safer Brand 16 oz. Caterpillar Killer II Concentrate kills worms and caterpillar stage insects but has no effect on birds, earthworms, or beneficial insects when used as directed. The caterpillars and worms that are damaging your plants will stop feeding immediately after ingesting, which is known scientifically as Bacillus Thuringiensis var. Kurstaki (B.t. for short).Use in late afternoon or on cloudy days since the BT breaks down in sunlight. Controls tent caterpillars, gypsy moths, cabbage loopers, tomato horn worms and more. Safer Brand Caterpillar Killer is OMRI Listed and can be used up until the day of harvest.

Review: Christmas In July thanks to Safer Brand 5163 Caterpillar Killer II Concentrate - UPDATE for 2020.... It's official. Not a SINGLE corn ear worm this year. Follow my review below and you'll never lose corn to that fish bait again! This stuff is dynamite! --------------------------------------------- If you have a problem with corn ear worms I hope you'll stick with this piece. It's my Christmas present to your garden. I have been planting corn in the same location for nearly 40 years so I know most of the tricks nature is liable to throw. This year I didn't have the perfect storm early in the season to leave the corn patch a tinkertoy mess. And we got enough rain and at the right time for a change so it was shaping up to be a great corn year. Corn, btw, gives the most ROI in growing pleasure. You really get a lot of bang for that little kernel. I LOVE just watching the stuff grow. Watching the honeybees at work etc. Love it! Anyway I always grow Golden Queen...which after years of experimentation works the best for me. This year I planted 5 rows, 60ft long. It's a back yard garden. Last year I bought Safer Brand 5163 Caterpillar Killer II Concentrate as an afterthought and sprayed at the corn a time or two and as usual 1/3 of the crop got gnawed. When shucking time comes normally on most of the ears I have to lop off the top....sometimes all the way to the middle. I live in corn worm heaven. Always have. We get very few perfect ears, and it's always a surprise when the queen ear of golden queen pops up un-gnawed. So I put most of the bottle into the fridge unused. Right next to the ketchup. Eyed that bottle all winter! This year I decided to go all out so at the first sign of silk I started spraying every other day up until about a week before harvest when I just got tired of doing it. Ha. Keep in mind that I was using the bottle I had held over a year in the refrigerator. I also sprayed my 32 tomato plants every other day. It may have knocked the horn worms back but not completely. In my case it probably didn't hurt but I eventually had to nuke them with a more lethal product. Put it that way. To be fair the jury is still out on tomatoes here. Back to the corn.... Last week I shucked out 162 ears on the first pick. Folks! I NEVER HAD SO MUCH FUN SHUCKING CORN! Out of that 162 I had to nip the tippy top out of 7 or 8 ears tops...and that looked to be from weevil chewing and not much of that. But out of 162 ears NOT ONE SINGLE EAR WORM!! Not a one! No sign. No worm. No nothing but ears of corn that looked like they came straight off the show room floor! Bam zoom zowie! Real state fair winners! Yesterday we did the second pick and out of that 50 not a single worm. It's unnatural! Normally the second pick is horrible! This time....only great pristine non chewed perfect ears! Bottom line I'd say that in my nearly 40 years I'll never top this corn harvest. BTW, I tried BT 30 years ago in powder form. Then I couldn't find it again for another 25. I always remembered that stuff and that's what prompted me to look for it again last year. Now it's all over the place. Safer Brand 5163 Caterpillar Killer II Concentrate really is concentrated. Even after all that spraying I still have some left over. Judging by my experience you could spray at least 600ft/row with two gallons made with two tablespoons. I may have practiced overkill, doing it every other day....but it WORKED. Why take chances? Spray at the first sign of silk... Even spray where you think the second ear may form if your corn puts on more than one ear. Do it every other day. And spray FROM THE TOP, making sure that some of the spray juice gets inside the ear. Do that and you will also have PERFECT corn and I don't care if you live in Ear Worm County. Spray nearly up to harvest. Get mean with that greedy fish bait. Do that and when you harvest you'll be thankin' me!
Review: Great stuff in the battle of army worms, and fruit borers with eggplants and peppers - This stuff works it’s not a biohazard I have a small Pascal sprayer I have finally figured out how to keep the army worms off my egg plants and peppers you may have to reapply there if it rains but after a few applications you’ll notice that there’s no more fungus no more leaves cut off no more holes in your eggplants. Bravo this is a great solution to having all of your eggplants and peppers damaged. And it’s super easy to use. I keep my little hand sprayer loaded and spray my plants in my earth box after it rains

## Features

- Kills caterpillars, gypsy moth larvae, worms and cabbage loopers
- Effective method of eliminating your garden or field of the tomato hornworm without environmental concerns or harm to beneficial insects
- Can be used up until day of harvest
- OMRI Listed and compliant for use in organic gardening
- Contains bacillus thuringiensis var Kurstaki 98.35 percent

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B00GVKZG8E |
| Active Ingredients | Bacillus Thuringiensis subspecies Kurstaki strain SA-12 solids, spores, and Lepidopteran active toxins 98.35%, Other Ingredients 1.65% Active Ingredients Bacillus Thuringiensis subspecies Kurstaki strain SA-12 solids, spores, and Lepidopteran active toxins 98.35%, Other Ingredients 1.65% See more |
| Best Sellers Rank | #10,844 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #73 in Insect & Pest Repellent Spray Concentrates |
| Brand | Safer |
| Brand Name | Safer |
| Customer Reviews | 4.5 out of 5 stars 3,090 Reviews |
| Global Trade Identification Number | 00024654516304 |
| Included Components | Safer Caterpillar Killer Multiple Insects 16 Oz |
| Item Form | Liquid |
| Item Type Name | Safer Brand 5163 Caterpillar Killer II Concentrate, 16 oz |
| Item Weight | 1 Pounds |
| Liquid Volume | 16 Fluid Ounces |
| Manufacturer | Safer |
| Model Number | 5163-6 |
| Part Number | 5163-6 |
| Target Species | Insects |
| UPC | 024654516304 |
| Unit Count | 16.0 Fluid Ounces |
| Warranty Description | Warranty |

## Product Details

- **Brand:** Safer
- **Item Form:** Liquid
- **Item Weight:** 1.02 Pounds
- **Liquid Volume:** 16 Fluid Ounces

## Images

![Caterpillar Killer II with B.T. Concentrate - Image 1](https://m.media-amazon.com/images/I/81OGpyaqiRL.jpg)
![Caterpillar Killer II with B.T. Concentrate - Image 2](https://m.media-amazon.com/images/I/61k+cnqmXbL.jpg)
![Caterpillar Killer II with B.T. Concentrate - Image 3](https://m.media-amazon.com/images/I/61hZenrRpEL.jpg)
![Caterpillar Killer II with B.T. Concentrate - Image 4](https://m.media-amazon.com/images/I/61I0r7I6BtL.jpg)
![Caterpillar Killer II with B.T. Concentrate - Image 5](https://m.media-amazon.com/images/I/61ZfljScm4L.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: How well does this work on fungus gnats?  I have to water every day and the yellow sticky flags can't keep up.  Thank you**
A: There are different subspecies of Bacillus thuringiensis, and they each kill different things. Bt is very specific. This product contains Btk, which is Bacillus thuringiensis var. kurstaki. It kills caterpillars, i.e., the larvae of butterflies and moths. It won't kill fungus gnats. You want Bti, Bacillus thuringiensis var israelensis. Bti kills the maggots of a certain subfamily of flies that includes mosquitoes, black flies, and fungus gnats. Some products that contain Bti are Gnatrol, which is a powder, and Mosquito Dunks/Mosquito Bits, which come carried on chunks of stuff made of corn. The specificity of Bt is what makes it excellent for people who have concerns about the environment and don't want to kill bees, worms, and other beneficial creatures, but it also limits its use. You can't spray it and expect it to kill all the bugs it makes contact with the way that many synthetic chemical pesticides do. You need to know what you want to kill and get the right formula for it.

**Q: Will this product harm our medicinal herbs? I don't want to spray if all of my flowers will die..we'd rather be stuck plucking the little %$&#ers....**
A: The description here on Amazon says it’s safe..  But the directions on the bottle say it’s poison.  It says harmful to people and animals, and to wash hands thoroughly after any contact.  Now I’m wondering is I can spray my tomatoes.

**Q: How long will a bottle last and retain it's effect last if stored correctly?**
A: This bottle of BT is a concentrate, so you'll need to mix the appropriate amount from the bottle in another sprayer-type applicator (the amount of BT to use depends on the capacity of your sprayer).  During the active growing period, the label recommends application once per week or after rain for best caterpillar control.  I personally have used this product before, and it lasted a long time when capped and stored out of extreme heat/cold.  The amount you'll use will depend also on the size of your garden.  This stuff will keep the common cabbage loopers and tomato hornworms OUT of your produce, along with other common lepidoptera larvae.

**Q: How much per gallon?**
A: We recommend mixing 1 tablespoon of concentrate per gallon of water.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Christmas In July thanks to Safer Brand 5163 Caterpillar Killer II Concentrate
*by N***N on July 11, 2019*

UPDATE for 2020.... It's official. Not a SINGLE corn ear worm this year. Follow my review below and you'll never lose corn to that fish bait again! This stuff is dynamite! --------------------------------------------- If you have a problem with corn ear worms I hope you'll stick with this piece. It's my Christmas present to your garden. I have been planting corn in the same location for nearly 40 years so I know most of the tricks nature is liable to throw. This year I didn't have the perfect storm early in the season to leave the corn patch a tinkertoy mess. And we got enough rain and at the right time for a change so it was shaping up to be a great corn year. Corn, btw, gives the most ROI in growing pleasure. You really get a lot of bang for that little kernel. I LOVE just watching the stuff grow. Watching the honeybees at work etc. Love it! Anyway I always grow Golden Queen...which after years of experimentation works the best for me. This year I planted 5 rows, 60ft long. It's a back yard garden. Last year I bought Safer Brand 5163 Caterpillar Killer II Concentrate as an afterthought and sprayed at the corn a time or two and as usual 1/3 of the crop got gnawed. When shucking time comes normally on most of the ears I have to lop off the top....sometimes all the way to the middle. I live in corn worm heaven. Always have. We get very few perfect ears, and it's always a surprise when the queen ear of golden queen pops up un-gnawed. So I put most of the bottle into the fridge unused. Right next to the ketchup. Eyed that bottle all winter! This year I decided to go all out so at the first sign of silk I started spraying every other day up until about a week before harvest when I just got tired of doing it. Ha. Keep in mind that I was using the bottle I had held over a year in the refrigerator. I also sprayed my 32 tomato plants every other day. It may have knocked the horn worms back but not completely. In my case it probably didn't hurt but I eventually had to nuke them with a more lethal product. Put it that way. To be fair the jury is still out on tomatoes here. Back to the corn.... Last week I shucked out 162 ears on the first pick. Folks! I NEVER HAD SO MUCH FUN SHUCKING CORN! Out of that 162 I had to nip the tippy top out of 7 or 8 ears tops...and that looked to be from weevil chewing and not much of that. But out of 162 ears NOT ONE SINGLE EAR WORM!! Not a one! No sign. No worm. No nothing but ears of corn that looked like they came straight off the show room floor! Bam zoom zowie! Real state fair winners! Yesterday we did the second pick and out of that 50 not a single worm. It's unnatural! Normally the second pick is horrible! This time....only great pristine non chewed perfect ears! Bottom line I'd say that in my nearly 40 years I'll never top this corn harvest. BTW, I tried BT 30 years ago in powder form. Then I couldn't find it again for another 25. I always remembered that stuff and that's what prompted me to look for it again last year. Now it's all over the place. Safer Brand 5163 Caterpillar Killer II Concentrate really is concentrated. Even after all that spraying I still have some left over. Judging by my experience you could spray at least 600ft/row with two gallons made with two tablespoons. I may have practiced overkill, doing it every other day....but it WORKED. Why take chances? Spray at the first sign of silk... Even spray where you think the second ear may form if your corn puts on more than one ear. Do it every other day. And spray FROM THE TOP, making sure that some of the spray juice gets inside the ear. Do that and you will also have PERFECT corn and I don't care if you live in Ear Worm County. Spray nearly up to harvest. Get mean with that greedy fish bait. Do that and when you harvest you'll be thankin' me!

### ⭐⭐⭐⭐⭐ Great stuff in the battle of army worms, and fruit borers with eggplants and peppers
*by E***E on September 20, 2025*

This stuff works it’s not a biohazard I have a small Pascal sprayer I have finally figured out how to keep the army worms off my egg plants and peppers you may have to reapply there if it rains but after a few applications you’ll notice that there’s no more fungus no more leaves cut off no more holes in your eggplants. Bravo this is a great solution to having all of your eggplants and peppers damaged. And it’s super easy to use. I keep my little hand sprayer loaded and spray my plants in my earth box after it rains

### ⭐⭐⭐⭐ Works Pretty Good
*by J***M on September 12, 2025*

Just what you need for your garden crawlers that are not invited to the harvest party.

## Frequently Bought Together

- Safer Brand 5163 Caterpillar Killer II Concentrate, 16 Oz For Insects
- Chapin 20000 Made in USA 1 -Gallon Lawn and Garden Pump Pressured Sprayer, for Spraying Plants, Garden Watering, Weeds and Pests, Polypropylene, Translucent White
- Safer 5118-6 Insect Killing Soap Concentrate - Insecticidal Soap for Plants - Kills Aphids, Whiteflies, Thrips, Spider Mites, and More - OMRI Listed for Organic Use

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.dk/products/4355848-caterpillar-killer-ii-with-b-t-concentrate](https://www.desertcart.dk/products/4355848-caterpillar-killer-ii-with-b-t-concentrate)

---

*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-05-24*