Building a Breeding Cage

• 1). Using the lumber and screen, construct a rectangular cage with a door for the butterflies. The breeding cage should be large enough to allow free flight, yet small enough to allow you to reach all areas inside. Use chicken wire around the lower edge of the cage, if built outside, to help prevent predators from entering.
  
  
• 2). Add host plants in pots or planted in the ground inside the cage. Butterflies require different plants for each species, and will usually only lay eggs on the plants their caterpillars will eat.
  
  
• 3). Create a watering station out of a shallow container, or one filled mostly with pebbles or sand, to prevent drowning. Although most adult butterflies do not need to eat, they will want water.
  
  

Breeding Butterflies

• 1). Determine the sex of your butterflies before releasing them into the cage. A female butterfly has a smooth tip to her abdomen, while a male has claspers intended to hold the female during mating.
  
  
• 2
  During mating, also called pairing, butterflies are connected at the end or their abdomens.Jupiterimages/Photos.com/Getty Images
  
  Watch your butterflies in the cage for signs of mating. This may take a few hours to begin. If no pairing off occurs, it can be done by hand. Taking a male and a female butterfly, open the male's claspers by gently squeezing the abdomen, then attach the claspers to the female before releasing.
  
  
• 3). After pairing off, continue to observe closely for egg-laying. The female will be seen walking over host plants slowly. Some species lay eggs individually, while others lay eggs in clumps.
  
  
• 4). Remove the eggs from the breeding cage. Eggs will need to be washed in a sterile solution to prevent the spread of disease, and hand-rearing will have better results than allowing the caterpillars to fend for themselves.