Small grow area, but plenty of vertical room.

I'm doing a small closet grow with 2 plants and I'm pretty limited for grow space, however I have almost 2m of vertical. Is there a way to grow my plants tall without branches stretching all over my grow space? Or some way of maximizing my yield for limited space? Both plants are 4 weeks old now.

Also what are the consequences of overcrowding? I'm guessing shitty buds because the light can't reach the budsites when there's too much plant in a small space?

buuuuuuuuump

Tying them up is about as good a suggestion I can come up with. Pipe cleaners, garden wire or whatever will do the trick. Just make sure the plant it self has plenty of support if you plan on making it grow tall, some bamboo cane or something along those lines will do the trick.

get some 4 foot t5 fixtures and attach them to the walls surrounding the plants. What are you currently using for light? Sidelighting is going to be key here i think.