Silkworms eat mulberry leaves exclusively in nature. Silkworm farms and manufacturers that keep the worms have the option to feed their worms a special artificial mulberry diet.
Newborn silkworms must be fed young mulberry leaves because they are more tender than the older leaves; their mouths will not be able to eat the older leaves right away. A very important step in feeding silkworms is to make sure that the leaves are free of pesticides. The moment that silkworms hatch they must begin to feed immediately. They must be fed constantly because they do not travel to find food. The larvae stay right with the mulberry leaves or tree, from the moment they hatch; this feeding will continue for 2 months as they go through four different molting periods to reach their full length of about 2 inches. Once they have reached this point, they are ready to spin their cocoon for the next part of their life cycle.
The silk cocoons that the worms are prized for take 5 days to be spun around the worm's body. The majority of the worms never make it to the moth stage due to being killed when the silk cocoons are gathered. The ones that do live and reach the next stage are dependent on humans for food and shelter just like the worms, though their life span is short. Both the male and female die after mating and laying eggs.