different size plants

hello! i have 5 plants in my mini grow room right now. i have a problem though; 3 of them are close to being tall enough (12 in) for me to switch them to a 12/12. the other two however are only about half that size. this is my first time growing and i'm not exactly sure what to do in this situation. i don't have a lot of room or equipment at the moment so i cant exactly set up another full grow room. the seeds were all different so i understand the size difference. could i just put a florescent bulb in a lamp and keep it with my two shorties? i would wait and let the other 3 just grow but unfortunately my space isn't that tall. would it be okay if i switched the little guys over while they are this little?? they were all started at the same time. please help!!!
thanks!

You can raise the shorter plants so that the canopy is even below the light. They are mature enough to flower if the nodes are alternating.

ok thank you so much. i will definatly do that. would the root structure be just as strong for the two short ones as the tall ones?

thanks again!

Under the same conditions, they are probably close enough depending on the strains and pheno types.

You should probably switch because they will stretch for two more weeks..

I wish I would've learned to make the switch earlier years ago..