I also considered titling this post "Impeccable Timing."
Last week I discovered some insect damage to my Brussels sprouts. I spent the weekend taking pictures fully intent on a blog post about it. Then my Aunt Kathy and Uncle Dave stopped in for a visit. She really wanted to see my garden because she's getting back into it now that she's retired and getting over some serious health issues. And her questions about organic solutions to insect damage were exactly what I was going to cover in the post.
So, Aunt Kathy, this blog post is for you.
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Two weeks ago we had some pea size hail come through with a storm front. The next day I noticed damage to the Brussels sprouts. Now, keep in mind these poor plants have had a
really rough winter, so it seemed appropriate they were getting beat up again. But upon further examination, and comparing what I saw on them compared to elsewhere in the garden, I discovered it wasn't hail damage at all. Hail hit the entire garden, but the damage I saw on my fall planting Brussels sprouts didn't match what I saw on the transplants I put in a few weeks ago.
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| Holey Brussels Sprouts |
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| Not Holey Brussels Sprouts |
And then upon closer inspection, I found the culprits.
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| Cabbage worms! |
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| More cabbage worms! |
Cabbage worms! And come to think of it, I believe I saw the butterfly (adult) form of these guys the same day I was planting the spring transplants. That may explain why I don't see damage (yet) on the other plants.
So now I'm in control mode. If you are not squeamish there is one sure-fire way to get rid of these guys - hand removal. Conveniently I have some willing accomplices for this task.
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| The willing accomplices. They work fast. |
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When you have worms this big there are some limitations on what you can use for chemical control. I turn to my trusty garden dust for something like this. It kills them quickly, and that's important to me given how fast the cabbage worms can devour a plant at this stage of development.
Personally I like the dust because I can see where it lands, but the same chemical is available in spray form too. The active ingredient is carbaryl, which is what is found in most "garden pest" products you can find in any garden or home store.
Now that I know the butterflies are active I'll be switching into prevention mode too. For that I like to use a different product type.
This uses
Bacillus thuringiensis bacteria, something naturally occurring in the soil but at higher concentrations it kills many worms and caterpillars that attack garden and farm crops. It is labeled for use in organic gardening (Aunt Kathy, this is what you asked about). Those of you who follow this blog know I'm all for the right tool for the right job, so why I like it is because it is very effective when the cabbage worms are very, very small. But when the worms get to be the size of the ones I found it doesn't work as well. It's also a spray, which means I can get it to stick in places that I can't get the garden dust, which also happen to be the places the caterpillars hatch and get their start. I used to be able to find
Bt products at my local big-box store but now I'm having to buy it from my favorite online
gardening retailer.
Any pesticide, whether it is a chemical dust or a bacterial spray, does have safe handling instructions and limits on when you can harvest the vegetables. Always read the label before use. Regardless, you should always wash vegetables thoroughly if they have been treated with any product for pest control.
I've looked into using
barrier fabrics for the garden, but given the way my cats and chickens like to destroy things I don't know if it will work for my situation. I did buy a few at an end-of-season sale last year and I'm going to try it on my
squash plants because chemical control doesn't work as well for those pests.
As for the chickens, they are not as discerning in terms of eating the worms and leaving the plants alone. It will be a while before this broccoli plant recovers.