Picking the hornworms off the plants reminded me of the plants I saw at Costco this spring. They were very large planters, probably around 6 or 7 inch. They would have been ready a bit earlier than the 4 and 5 inch planters that I started with this year.
So far the crop has been pretty good. The plants are sucking down enough water that I have to fill the earthboxes twice a day.
Here's a picture of a small hornworm, about the size of a pencil. Larger worms get to be the size of a persons little finger or larger.