Preparing Potted Plants for use in Netting Cages

Much pleasure and knowledge can be gained from watching the development of butterflies. Three factors normally promote good results:
1/ Good healthy plants
2/ The avoidance of predators
3/ The right temperature and humidity conditions

Start by potting up younger plants using pest and weed free potting compost. Covering the holes in the base of the pot with a pad of thin fibre-mat or a similar porous material stops pests from entering but still allows free passage of water and air.

A wide range of pests and parasites including woodlice, weevil larvae, slugs, beetles, centipedes, earwigs, ants, and spiders can accumulate on the plant or in the soil, perhaps because the plant was left unsleeved or because it was necessary to use a soil other than potting compost. These pests can dealt with by totally immersing the pot, soil and plant in water for two days before introducing the larvae. Most unwanted visitors drown or float off and can easily be hand picked. Aphids can be killed by using an insecticide spray as directed, but not with larvae present. Be careful when selecting your insecticide - many will still kill larvae several weeks after application.

To ensure the health of the food plant, clip off old growth, water regularly and feed with liquid fertiliser to encourage the growth of new young leaves which most larvae prefer. If the plant is completely consumed it is possible to put a cut plant in a water jar in your insect cage. The neck of the jar should be blocked off using a wad of cotton wool, to prevent the larvae entering and drowning.

Keeping an appropriate temperature and humidity are important. Natural outside conditions are usually best for British butterflies. Some species, such as downland types, thrive in good sunlight. Others, for example woodland species, require shade. Under greenhouse conditions or on a sunny indoor windowsill, very hot and dry conditions may be created which can quickly kill larvae which expose themselves. If in doubt, it is safest to choose light but shaded situations.

Please note that these hints should be regarded as general guidance and do not guarantee breeding or rearing success. For common sense ethical guidelines about rearing butterflies and other excellent supporting information, please see Steven Cheshire's 'British Butterflies' site.
Enjoy caring for your butterflies and happy rearing!