TWO questions.... Help Please!

for3ver3xiled

Active Member
Is a 400 watt HPS light powerful enough for 2-3 plants? How high should I put it above the plants? What should the light cycle be? AND..... How do I know when to start flowering.... Doing a 12/12 or something?
 

MaNgOsRoCkWiThMaRyJ

Active Member
Is a 400 watt HPS light powerful enough for 2-3 plants? How high should I put it above the plants? What should the light cycle be? AND..... How do I know when to start flowering.... Doing a 12/12 or something?
400 watt Hps will be good... the light time should be: 18 hours ON/ 6 hours OFF.....wait till plant are 6-8 weeks old.. then switch light schedule till 12/12
 

jordisgarden

Well-Known Member
heres what i have under my 400 hps...i fit 15 in 2 gallon bags nooooooo problem. the only thing is when i flower i added 2 100 watt lamps for side light.
the otherr 2 100s thickened the shit out of em.
3 plants under a 400hps will be absolute fucking monsters....
 

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Is a 400 watt HPS light powerful enough for 2-3 plants?
Yes and no. You could have a dozen tiny plants or just one huge one. Rather than thinking in terms of plant numbers, it's more relevant to think in terms of grow area. Then you can look at the number of watts per square foot. The optimum is about 50 Watts per square foot. So a 400 W should ideally cover about 8 square feet.


How high should I put it above the plants?
3 ft, maybe closer if you can use a fan to blow the air between the plant and the light. Use your hand to test at the max height of the plants, if it feels too hot for your hand, then it's too hot for the plant.

What should the light cycle be?
For vegging, make sure the plant doesn't get more than 11 hours of uninterrupted dark. 18/8 and 24/0 or anything in between is fine. The more light they get, the faster they'll grow. Conversely, the less light they get, the taller they'll stretch.



How do I know when to start flowering.... Doing a 12/12 or something?
Veg them until they start to show sex or until they're as big as you want them to be. Bear in mind that they'll probably double in size during the first two weeks of 12/12
 

jordisgarden

Well-Known Member
1 mine is in a 3 by 3 area and it gives great light penetration to 10 plants in 2 galllon bags easy
2- take your hand start at the bulb lower it until the heat isnt so intense theres where ya want it. you will either need to stack you plants on totes and drop em down as they grow taller or you need a pully system that raises the light as they grow
3-you can flower whenever you want. i usually flower at 6 weeks when my plants reach 3 feet. flowered at 3 ft theyll end up putting on a foot maybe a little less . the longer period of dark means the plant is gonna stretch to the light. thats why the grow so much taller in flower..
here are some that i grew under my 400 at the same time ....a lot of this is gonna be trial and error, you will learn something new with every grow and youll get to know what works best for you....someone told me id never get 15 under the 400 but proof is in the pudding...again though i dont go for the 7 foot plants i keep em at about 4 feet. then i tie em down so the branches fill in nice
 

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