how long can you veg plants under a T12 2-40watt??

[rhino1111]

ive been waiting for my 400watt HPS, im vegging 4 plants, plants are on between 2-4th true node. im wondering how long i can veg these guys under this before the light isnt enough??

I have a T12 2-40watt 7000k. 1" away from tops.

oh and how far should i keep the 400watt HPS away from 3-4week old plants when i get the HPS. i read something like 12"-24" not sure what would be the best height for young seedlings.

 

[RawBudzski]

just long enough until you realize its not enough and go buy a 600w digital ballast.

 

[rhino1111]

lol im waitin on my 400watt...im just wondering how long i can veg them for.

 

[turdnugget420]

Help us help you, put some pics in the post. Also, to answer your question about distance to keep from your HID light when you get it. You will want to test the heat with your hand, that's by far the best test. You can have the tops of your plants at the point where you hand feels comfortable under the light, not able to feel hot heat emitting from the light source.

 

[rhino1111]

https://www.rollitup.org/newbie-central/383978-first-time-grower-grow-journal.html


pics of my plants. no pics of light but theyre long. 2-40watt 7000k fluorecent. T12 fixture.

 

[smokebomb1]

your t12's will work up to about a month to maybe 6 weeks then the plants will be too big for the light, it is best to start your 3 to 4 week old plants at around 24 inches when switching to hps, helps the plants get use to the change in light. then work your light slowly down to desired hight every day or so. i find this helps not to heat burn the leaves also. hps in the 400w range isnt really all that hot so you can get it within 8 inches or so. hope this helps.

 

[rhino1111]

your t12's will work up to about a month to maybe 6 weeks then the plants will be too big for the light, it is best to start your 3 to 4 week old plants at around 24 inches when switching to hps, helps the plants get use to the change in light. then work your light slowly down to desired hight every day or so. i find this helps not to heat burn the leaves also. hps in the 400w range isnt really all that hot so you can get it within 8 inches or so. hope this helps.

man i really appreciate it, straight up answer.. all i needed to know answered. thanks alot bro. +rep