Trying to raise my 17' babies any help

Finally I have found the right place. Well not only am i new to rollitup but to growing to. I have just recently received four baby plants all with their own 4x4 in. green container which feels a little like Styrofoam. i have kept them under lighting but i need to know what to do next and quickly before all is lost. They are about15'-19' inches any help would be remembered.