But a single hornworm in the garden can do a lot of damage. Yesterday I noticed a hornworm--no, make that three hornworms--actively eating the purple cherry tomatoes I have planted in a patio pot. The culprit is hanging from the tomato branch. Notice the almost-eaten cherry tomato at the end of the stem.
Because these guys seem to appear overnight (and usually in multiples), it is important to check the plant frequently. Here is a closer look at the caterpillar you are looking for.
Their natural camouflage is so effective that often they will have done significant damage before you spot the caterpillar himself. So, even if you have not seen caterpillars, here are some clues that you should closely examine the plant. First, partially eaten fruit.
Second, branches that have been stripped of their leaves.
So how do you control them? By far the easiest and most environmentally-friendly way is to handpick and crush them. Or you can drop them in a bucket of soapy water as we did with the Japanese beetles. Picking them off is a very icky task and not to be undertaken by the faint-hearted. If you prefer not to touch them, you can use a Bt (Bacillus thuringiensis) product, which will kill them when they ingest it. Or, as I did, you can point them out to your husband (or some other less-squeamish person) to do the disgusting deed.