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Hornworms by Brionna McCumber

Gardeners in Colorado may find large green caterpillars with an iconic horn on their plants every summer—these are hornworms! Tobacco hornworms (Manduca sexta) feed on common garden crops, often leading to conflict with humans. These very hungry caterpillars are defoliators, damaging plants such as tomatoes, peppers, potatoes, and eggplant. While the caterpillars use crops as a food source, which could be seen as negative, the moths provide a critical step in reproduction for the plants via pollination.


Carolina Sphinx Moths (Manduca sexta), also called Hummingbird moths, are the adult form of hornworms. They are known for their unique ability to hover mid-flight. Combined with the use of a special elongated proboscis, these moths are especially important for plant species with long tubular flowers that other pollinators cannot access or pollinate. 
The Gardens on Spring Creek Butterfly House wants to highlight the importance of these specialized pollinators in our native Colorado ecosystems. We recommend that those who have hornworms in their garden attempt to relocate these creatures instead of bringing them into our facility. These animals eat many more things than just tomatoes! They are not picky and can host on a large variety of plants. Other plants that these caterpillars may find attractive:
  • Potatoes
  • Horse nettles
  • Eggplant (Solanum)
  • Peppers (Capsicum)
  • Jimsonweed
  • Thorn Apples (Datura)
  • Wild Tomatoes (Lycopersicon)
  • Tobaccos (Nicotiana)
  • Cape Gooseberry
  • Tomatillos
  • Husk Cherry (Physalis)
  • Petunias
  • and many more! 
You can help support local wildlife and pollinators by relocating hornworm caterpillars to a space where they can eat and grow without being a nuisance to your crops. Please help us keep wildlife, wild! 

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