Step 1 : Introduction to the question "What do silkworms eat?"
...A silkworm exists when a silk-moth (Bombyx mori) is in its larvae stage. It is an important insect economically as the silkworm is the world's primary producer of silk. The silkworm lives on a exclusive diet of mulberry leaves. Domestication of the silkworm has evolved this insect to the point that it is completely dependent on humans for reproduction. This is a result of centuries of selective breeding for commercial silk production. Wild silk-moths remain but are different from their domestic relatives and are not a viable source for silk production. Source: EverythingSilkworms.com.au