Answer: Unfortunately I am not certain which kind of plant you are calling a late bloomer, but by the distinctive description this sounds like a hornworm of some sort such as those that most commonly bother tobacco and tomatoes. It is the caterpillar of the sphinx or hummingbird moth. You can pick it off by hand, often just the one caterpillar causes an amazing amount of damage in just a short time. Here is a photo and some additional information you may find interesting. You may need to cut and paste the comnplete url into your browser to make it work correctly.
I hope this helps!
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