Hornworms: Where is a parasitic wasp when you need one?

I knew they were there even though I couldn’t see them just yet. I could however see the damage they left behind:

I’ve been finding a few small hornworms on tomatoes in another part of the garden, so I knew one had to be in there somewhere. I searched among the foliage for him carefully. It took a while to spot him, then almost as an optical illusion he appeared on the stem he was perched on all along:

It was almost like drinking a magic potion that gave me special abilities to see invisible things, because just then another one appeared on a leaf near the first one. “Ah, two!” I thought as I ran inside to get a fresh jar of soapy water and the camera.

As I scooted down on one knee to focus the camera on the hornworms, I was alarmed to see two more!! There were four very large hornworms on one tomato plant!

Now these guys creep me out, so after taking a few hurried pictures, I donned a glove and reached in, snatched them off the plant, and quickly dropped them into the jar of soapy water.

I’ve been watching my tomatoes carefully for signs of disease and have found and killed quite a few small hornworms over the last few weeks. I don’t recall ever having such a population. Curious about their lifecycle, I did some research and was surprised to learn that their eggs hatch in only 3-5 days. Also, the ones in my garden are tobacco hornworms, not the expected tomato hornworms. The difference is in the horn color and markings on the body. Tobacco hornworms are usually green with seven diagonal white lines on the sides and a curved red horn. Tomato hornworms have eight V-shaped marks on each side and their horn is straighter and blue-black in color. Both feed on the foliage of various plants from the Solanaceae family.

The eggs can be found on the underside of leaves and sometimes even on top. They are translucent green and measure about 1 millimeter in diameter. Tobacco hornworm life spans over 30 to 50 days. The eggs hatch into green larvae which can grow to 70 millimeters long. The larvae become the tobacco hornworm pupa that finally matures into the adult Sphinx moths or hawk moths.

A new task has been added to my evening routine. Now armed with gloves and a large jar of soapy water, I hunt hornworms to keep my tomatoes safe.