Who
Hornworms (Family: Sphingidae). These large caterpillars often reach 5 inches in length and are most easily identified by the “horn” protruding from the tip of their abdomen. Hornworms typically do not spin a cocoon but rather pupate “naked” on top of or in the soil.
What
These large caterpillars will eat, and eat, and eat, and eat not only tomato plants but eggplant, potato, and peppers. You will see frass (fancy word for bug poo) and lots of little munch marks on your leaves! Look especially for stems with wilted leaves or no leaves at all.
When
Depending on your area, these are generally active as caterpillars during the spring and fall.
Where
The family is found everywhere in the world (except Antartica) but is most dense in tropical locations.
Why
Some species of Sphingids such as the tomato hornworm (Manduca quinquemaculata—say THAT 5 times fast!) and the tobacco hornworm (Manduca sexta) feed primarily on plants in Solanaceae. If ya didn’t know, Solanaceae is the family of plants that contains tomato and its relatives.
How
These can easily be plucked off and relocated to a less worthy plant, but can also be disposed of at your discretion. There are also many biological controls available on the market that you can use such as a Bacillus thuringiensis (Bt) application.
Lauren’s Notes
Sphingid caterpillars are known as hornworms, but the adults are known as sphynx, hawk, or hummingbird moths! There are over 1,400 species of these wonderful pollinators. Many species are known to hover while feeding on nectar like hummingbirds. You may not know this, but the ability to hover is incredibly rare in the animal world. Sphynx moths are also some of the fastest flying insects coming in at 12 miles per hour (which is really fast for something that has a wingspan of less than 4 inches).