hydrangea macrophylla leaves Where are these little plants? In doors? Or out of doors? In 4" pots? They will need a balanced fertilizer soon. What are your plans for these plants? They should be acclimated to the real sun before being planted directly into the garden with extra attention to watering. They would work in large pots...up potted next into 1 gallon, then 2 gallon, then 5 gallon and possibly 15 gallon. Do you have winters? Plants in pots have their roots subjected to too cold and too hot temperatures which could kill the roots and thus the entire plant.
Lorel got the ID is this is correct!