I've got 5 little sprouts

Not too bad. I've got 5 more germinating, then I'm gonna start them in cups and germ 5 more. Don't want to do too many at once.
I want to see some growth and health right off the bat. Is there anything that I could do to the water before I water them? I think the next time I'm going to be out at my spot is Monday. I'm going to bring a gallon or two of water out with me to water the 5 little sprouts. Is there any household tricks I could do to get the right amount of nutrients in the soil? I don't have much money to spend or anything, but if there's something that could be put in the water to supply the nitrogen, phosphorus, and potassium? Also, I know that rotting plant material can have some good stuff in it...would maybe pieces of banana help the potassium in the soil...or would it just attract small animals to the grow spot??
I just want to get everything off to a good start. Any tips or tricks from experienced...or even inexperienced growers here. I'm looking to learn as much as possible about this so that I have a good outcome at the end of this growing season.