Lighting, lighting times, ventilation and stages

[b2ke]

So pretty much I'm about to start my grow and I'm going to start it with a teen clone. And I have a few questions I would gladly appreciate if any of you guys can answer any of them. Thanks

1. I was wondering if one 400w HPS light would work to grow my plant all the way to flowering and harvesting. If not what lights should I get instead?

2. For the lighting times during vegetation should i have it 18/6? and for flowering should i have it 12/12

3. The ventilation I understand I'm going to need a fan to blow the air out. But I was wondering if I'm going to need a fan blowing new air in or do i just need a fan inside to just blow air on the plant.

4. When will I know its time to start the flowering stage after the vegging stage? Like if there a certain length the plant needs to be.


Also here is my grow box design I drew out please feel free to comment on it.

 

[DEAN420]

1. yes

2. yes

3. you'll need an outtake fan, a small fan in the room moving air and a passive intake or intake fan to bring fresh in air.

4. grow your plants to half the size you'd like them to finish because they are likely to dubble or even tripple in hight once flowered.