Just planted some Poopship Destroyers

My friend gave me some poopship seeds so I germinated, and planted. they're about 3 inches tall, just starting to get their second set of leaves to complete the first 4. When do I add miracle grow?

You don't want to feed until 3-4 weeks into growth.
What type of strain is "poopship destroyer"? Besides the band I can't find any info on the strain.