Butterfly food plants

Butterflies spend their short lives seeking plants for food, shelter and places to lay eggs. The plants they use fall into two categories: host plants and nectar plants. Host plants provide food (mostly the leaves) for caterpillars, and nectar plants provide food (through the flowers) for the adult butterflies. Some plants serve both purposes.

Several species of native Aristolochia vine are host plants for Australia’s largest butterfly, the Cairns Birdwing. The female seeks out this host plant and deposits her eggs on it. After hatching, the hungry caterpillars start eating the leaves before pupating into a chrysalis. The vines don’t provide any food for the adult butterflies so they must search for nectar plants. A good place to see Cairns Birdwing butterflies and caterpillars are the Aristolochia vines growing along the western boundary fence of Flecker Gardens.

The Lacewing Vine, Adenia heterophylla, is a food plant for caterpillars of the beautiful Red Lacewing butterfly. The caterpillars are bright yellow and black – warning signs in nature that they are poisonous. Like many butterfly species, the toxin in the caterpillar comes from the poisonous leaves of the vine. Lacewing is also a host to the Glasswing and Cruiser butterflies.

When flowering, Lime Berry Trees, Micromelum minutum, attract large numbers of butterflies that feed on the nectar. It is a great tree to grow in Cairns gardens and attracts many species including Green Triangle, Brown Soldier and Jezabel butterflies. Lime Berry is in the same plant family as citrus and is a host tree for the Orchard Butterfly.

Little Evodia, Melicope rubra, is a host and nectar plant for the blue Ulysses butterfly, providing food for both the caterpillars and the adults. Little Evodia is small, fast growing and produces masses of flowers along the branches even as a small shrub. Another species of Evodia in the Wet Tropics is the Pink Evodia, Melicope elleryana, a much larger tree that grows to 35 metres. It is also a host tree for the Ulysses butterfly.

Most of the 11 species of Capparis in the Wet Tropics are host plants for Caper Butterflies. The plants are often seen with dozens of small white butterflies hovering around the plant. Most commonly seen around Cairns are Pearl White butterflies that lay eggs on the leaves of Coast Caper, Capparis lucida.

These are just a few examples of the relationship between plants and butterflies. For more information check out Garry Sankowsky’s book “A Field Guide to Butterflies of Australia – Their Life Histories and Host Plants”.