questions from a new grower

[bongo]

does cigarette smoke kill the plant. Also, it looks like there is white mold on the dirt itself. And when can i determine sex, they are about 6-7 inches.

[Zandor]

Smoke will clog the stomata so yes smoking around your plants is bad.

The white mold on the dirt is probably toxic salt build up, watch for nutrient lockout. It's a good bet there is no problem and you can just turn the soil and the next time you water it will dissolve back in to the system.