let your mother plant grow to about 7th-8th node, then clone away. you could get away with 15 plants under 400w, but how long r u gonna veg for, ? if to long its gonna b a bit tight but c wot happens, u learn from making mistakes, good luckHow long do u think i would have to let a mother plant grow b4 i can get atleast 12-15 clones off of it? And is that too many plants for a SOG under a 400 watter? Any help/replies are greatly appreciated, +rep