The Dreaded Hornworms

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Materlvr
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The Dreaded Hornworms

#1

Post: # 147802Unread post Materlvr
Mon Mar 24, 2025 5:23 pm

How can I prevent an hornworm attach? Does planting borage or peppermint help?

Thanks

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karstopography
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Re: The Dreaded Hornworms

#2

Post: # 147807Unread post karstopography
Mon Mar 24, 2025 6:02 pm

Look for the eggs. Remove the eggs before they hatch. If the eggs hatch, use something like Bt or spinosad per the label to kill the caterpillars. In my experience, these extracts will absolutely eliminate current hornworm infestations, but won’t prevent future infestations.
"No occupation is so delightful to me as the culture of the earth, and no culture comparable to that of the garden."
Thomas Jefferson

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worth1
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Re: The Dreaded Hornworms

#3

Post: # 147815Unread post worth1
Mon Mar 24, 2025 7:04 pm

Netting will help as well.
The darned things seem to grow overnight.
Worth
25 miles southeast of Waterloo Texas.

You can't argue with a closed mind.
You might as well be arguing with a cat.

tyrupp
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Re: The Dreaded Hornworms

#4

Post: # 147816Unread post tyrupp
Mon Mar 24, 2025 7:18 pm

hunt them down after dark with a black light

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Shule
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Re: The Dreaded Hornworms

#5

Post: # 147819Unread post Shule
Mon Mar 24, 2025 7:42 pm

Move to SW Idaho. I saw a hornworm here once, as a child. I thought it was awesome. I do see big moths that in theory could come from hornworms (they love Phlox), but I don't see the actual caterpillars anywhere, and we grow lots of tomatoes. Maybe it's just my garden.

Seriously, though, you probably don't want to move here just to grow tomatoes (you'd have to learn how to tomato garden all over again, and you might end up getting hornworms anyway).
Location: SW Idaho, USA
Climate: BSk
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pondgardener
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Re: The Dreaded Hornworms

#6

Post: # 147825Unread post pondgardener
Mon Mar 24, 2025 8:39 pm

I've been planting basil with my tomatoes on the end of rows and haven't seen any hornworms.
https://www.backyardboss.net/plants-tha ... -tomatoes/
It's not what you gather, but what you scatter, that tells what kind of life you have lived.

Mark_Thompson
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Re: The Dreaded Hornworms

#7

Post: # 147830Unread post Mark_Thompson
Mon Mar 24, 2025 10:05 pm

Nothing to add on preventing them, only had an issue once. Just wanted to share my picture

IMG_2539.png
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Wet and windy side of a Hawaiian island, just living the dream

AdrianaG
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Re: The Dreaded Hornworms

#8

Post: # 147841Unread post AdrianaG
Tue Mar 25, 2025 4:40 am

Keep a daily watch out for their poop which is almost pea size and pick them off.

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MissS
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Re: The Dreaded Hornworms

#9

Post: # 147868Unread post MissS
Tue Mar 25, 2025 10:43 am

Shule wrote: Mon Mar 24, 2025 7:42 pm Move to SW Idaho. I saw a hornworm here once, as a child. I thought it was awesome. I do see big moths that in theory could come from hornworms (they love Phlox), but I don't see the actual caterpillars anywhere, and we grow lots of tomatoes. Maybe it's just my garden.

Seriously, though, you probably don't want to move here just to grow tomatoes (you'd have to learn how to tomato garden all over again, and you might end up getting hornworms anyway).
Shule the moths that you are most likely seeing are the white-lined sphynx moth or the P. Modesta. Neither of these would be feeding in your garden other than to use flowers for nectar.
~ Patti ~
AKA ~ Hooper

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GoDawgs
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Re: The Dreaded Hornworms

#10

Post: # 147932Unread post GoDawgs
Wed Mar 26, 2025 8:13 am

karstopography wrote: Mon Mar 24, 2025 6:02 pm Look for the eggs. Remove the eggs before they hatch. If the eggs hatch, use something like Bt or spinosad per the label to kill the caterpillars. In my experience, these extracts will absolutely eliminate current hornworm infestations, but won’t prevent future infestations.
I agree. I've never used spinosad but the bT works wonders. Around here the hornworms usually show up in June so in late May I usually do a bT application on the tomatoes and that seems to work pretty well. When one finally does show up later, one more app usually takes care of it for the season.

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worth1
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Re: The Dreaded Hornworms

#11

Post: # 147940Unread post worth1
Wed Mar 26, 2025 10:37 am

Each horn worm has its plant that it eats more or less.
We have one that eats a wild vine down here doesn't bother anything else.
Worth
25 miles southeast of Waterloo Texas.

You can't argue with a closed mind.
You might as well be arguing with a cat.

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worth1
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Re: The Dreaded Hornworms

#12

Post: # 147941Unread post worth1
Wed Mar 26, 2025 10:40 am

Here's the difference between the tobacco hornworm and the tomato hornworm.
Worth
25 miles southeast of Waterloo Texas.

You can't argue with a closed mind.
You might as well be arguing with a cat.

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karstopography
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Re: The Dreaded Hornworms

#13

Post: # 147949Unread post karstopography
Wed Mar 26, 2025 12:46 pm

Only one we get on the tomatoes or peppers here are the Tobacco Hornworms. Never seen a Tomato Hornworm.
"No occupation is so delightful to me as the culture of the earth, and no culture comparable to that of the garden."
Thomas Jefferson

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worth1
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Re: The Dreaded Hornworms

#14

Post: # 147964Unread post worth1
Wed Mar 26, 2025 6:20 pm

That's all I've ever seen as well.
The dreaded tobacco hornworm on tomato plants.
Worth
25 miles southeast of Waterloo Texas.

You can't argue with a closed mind.
You might as well be arguing with a cat.

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