Ok i might be crazy...but does cat grass make your cat sleep?

My kitten always stays up until like 1 am every night being super hyper until finally falling asleep. That is, this is what used to happen. For the past 3 days, every night for my kittens goodnight snack I sprinkle in some homegrown cat grass and he falls right to sleep! Maybe I'm crazy and its just a coincidence, but do you think the cat grass is making my kitten sleep?