yes, they both last pretty long. My hornworm cup had about 20 horns in it. I had it over 3 weeks. What I do is take them out of the cup like every other day and remove them from the food so they don't grow as fast, cause they will grow at an unbelievable rate and they might get too big to feed off. I still had food left over and had already fed off all the horns. The silkworm cups last about a couple of weeks , well the food that is. There is usually way more silkworms inthe cups than the hornworms so the food goes quicker. I usually buy a pound of the chow and feed it to them if I have not fed the silks off.