Eggs should be kept in closed plastic containers to prevent them drying out. Typically, eggs will start out a white-grey colour, darkening to black as they near hatching. The darkening indicates the caterpillar is fully developed within the egg, and should then hatch within a couple of days. They will benefit from extra humidity at this time, which can be applied by finely misting the inside lid of the container - do not spray directly onto the eggs or allow them to sit in water droplets as this can drown the embryo or cause mould to grow, killing the developing caterpillar before it can hatch.

You can add leaves to their container once the caterpillars hatch, but do not add any prior to this as leaves will release moisture and this often causes the eggs to mould before hatching, killing them. Once the larvae have established and are feeding well, they can be moved to mesh cages or larger plastic containers if preferred. Additionally, larger larvae do very well on living host plants if you have some potted or in a greenhouse.

If you purchased the Owl Butterfly mixed eggs/caterpillars, they will accept any of the following host plants: Banana (Musa & Ensete); Ginger (Zingiber); Heliconia; Bamboo; Canna Lilies; Bird of Paraidse (Strelizia); Cypres grass; various Reeds and other broad-leaved grasses are also accepted.

Young larvae tend to live in groups, often moving around the host plants in a long line, 2-3 caterpillars wide and several in length - particularly when kept in a naturalistic setup such as a greenhouse. The early stages have a yellowish colour, changing to green and then brown as they grow, with a spiked head case.

In the wild in South and Central America, Owl Butterflies are considered a pest species on Banana plantations, where they can decimate entire plants overnight, quickly moving onto the next! Their vigorous appetite makes these caterpillars easy to rear in captivity, however.