You need to get bT in some form or other on those ASAP. Especially if they are attacking the new growth - which is their preferred target. I will tell you, hornworms are especially difficult to spot. They look exactly like a twisted leaf. We also have been attacked this year by some kind of dark olive-green/brown caterpillars. They are awful. Anyway, bT comes in powder, such as Dipple Dust, a ready-made spray such as Safer Caterpillar Killer or a concentrate that you can use in a pump sprayer.

Thanks for your comment, Ediej. I take it then that this is a worm-based problem.

I’ve found a product with BT where I live in Spain. Any additional tips on how much and how often to spray? By how much I mean drenching the plants or simply spraying a light coat? How many days between application? How long before I should see some results?

Thanks in advance for the extra input.

We coat the plants. And reapply after heavy rains, but not if it's just light sprinkles, that won't wash it off. You might still want to use the sulphur but give it a few days after applying the bT. That works more as a fungicide which helps slow down the progression of diseases such as wilt or blight. With gardening, and it seems especially tomatoes, it's always something. But the reward is SO worth it!

Thanks for your help, ediej!

I agree that it seems like there is always something (and that it's well worth it), so my final question is this: I've purchased orchid extract and see that it works pretty well for many things (fungicide, insecticide, foliar fertiliser). Would it be safe to just use the orchid extract in place of the sulfur with the BT spray at alternating intervals, say Monday orchid extract, Thursday BT, as a general keep-things-under-control treatment?

I've yet to try one tomato from these because of all of the problems they seem to encounter. I'm not ruling out my fault in these either. I'm a green gardener ;).

Sorry, it’s not orchid extract but nettle extract! Translation mistake 😝

I'm not familiar with nettle extract but if it works as a fungicide, it should be fine.

Thanks! I’ll post some updates once I get the products and start the application. Looking forward to some nice tomatoes now!

Hi Ediej,

I think we may have a misdiagnosis here. I was reading something when I stumbled upon a "black faeces deposits" which matched my particular problem. These bugs are called thrips. I am sure you've heard of them. This explains why I cannot find anything, and how literally new growth at the top of the plant, very small for a caterpillar, becomes spotted and has the spots on it. They thrive off of new growth!

Any idea how to treat this nasty problem?

If it is thrips you need 2 different products - Neem Oil and insecticidal soap. Use one and then rotate a week (and keep rotating) later to the other and spray thoroughly early of a morning. I also read that a silver foil mulch can help but I would worry that it would make roots too hot. But the worst part of thrips is they carry a bunch of diseases, most notably wilt. Not good.

Hi again ediej,

This morning I went out to inspect the garden, sure I would find thrips. Instead, and to my surprise, I found worms. You were right. I can't believe I missed them! Once I found the first one enjoying breakfast on some new growth, I found another, then another, and the count is endless. I had just sprayed BT the night before so I am happy to know that I don't need to buy yet another product.

I've attached a photo. The worms are small, but not invisible to the naked eye. No bigger than half of my finger's width, so roughly 1cm. The others I found were this size and even smaller. Some are green and others palish-yellow in color. I've taken some pictures below. Interestingly, this one was actually inside the leaf itself. When I opened the leaf, he had a line of webbing as it hung from the leaf. Any idea what specific type of worm this may be?

My question now is this: is it okay to use a foliar spray in addition to the BT, alternating days (about every 3 days a spray is used)? I ask because the leaves are fairly destroyed from these worms and the plant seems to be struggling at a foliar level. But I don't want to diminish the potency of the BT by spraying another foliar spray, even if it's on a different day. Also, is BT still the most effective spray for this type of worm? I assume it is as I read it's effective against all worms, but I want to make sure.

The size

(Even left a little black surprise, identical to the ones found on the plants. How generous.)

I would repeat the bT making sure to get it into any leaf that is rolled up and the backs of all the leaves. Not sure of exactly what kind those are, I'm sure some kind of moth. And yes you should be able to spray the foliar spray in a couple of days. Although a good fertilizer specifically for tomatoes, diluted down to about half strength, might be beneficial to encourage new growth.

thanks so much, ediej. I can’t tell you how I appreciate you taking the time to help.

Without wanting you to feel obliged, why do we dilute fertilizers to half strength instead of full?

ill do as you say and spray the BT again before I do the foliar spray (nettle extract), probably with 5 days of separation between the sprays as the infestation is bad. I can already see an affect, though. Found some worms this evening (24hrs after initial spray) and I found some worms dead or dying.

thanks a mil!