300w LED Grow Lights - Arrangement and other questions

[Derismith88]

This is my first grow and it has been quite fun learning about how this all works. I have two 300w Viparspectra lights. Currently I only have one plant going, but am curious what the ideal arrangement of the lights would be. At the moment I have them as you see in photo because it seems to give good coverage. However, wondering if it would be better if I had it so the long sides were parallel.

Also, after this harvest, I plan to plant some autoflowers in 3 gallon pots. I have two questions in anticipation of that grow: 1. How many plants do you think I could reasonably have going with two lights 2. In that scenario what would be the ideal arrangement of the light to give thebest coverage?

Appreciate any and all help!

[LuckyAcres]

You don't think one light is good enough? What's the coverage shown in the manual?

[Derismith88]

For one plant one should be fine, but since i bought two figure ill just leave them both on. The arrangement question was more for the most efficient way to arrange them assuming growing more than 1 plant. manual says 2x2.

I see you have the 1200w viperspectra what is the coverage on that?

[fozzy]

If you were to put them side be side. In a parallel like this [] [] about 1 foot apart.
It should cover 3x3 during veg and 2.5x2.5 during flower. I would keep them at 18" during veg and 12" during flower. Also keep the lights about 1 foot from the wall.
Good luck!

[fozzy]

I forgot something. For plant count you could have 1-9 just depends how big you veg them.

[Derismith88]

Thank you! ha I wanted to put a symbol likethat when writing the post, but wasn't sure how to mimic it. That's the arrangement im going to go with then, thank you for the suggestion for the distance as well!

[bobsakamoto]

hi deri. i too am on my first grow and couldn't agree more about how fun it has been learning about everything. i plan on using a combination of LED and MH/HPS. i have done a s*#t ton of research on lighting and when i was planning placement of my LEDs i found a really helpful diagram that basically shows you 3dimensionally the best way to place your lights. of course i can't find where i saw it right now... ...but i'm gonna describe it and maybe that can point you in the right direction. it was basically like if you placed say a sheet over your light and it stayed straight at the corners. so that means that the further up your light is the larger its footprint so to speak. if you have it very close then maybe your footprint is only a few inches all the way around than the actual size of your light. but if you've got it 40" off the ground then your footprint would be much larger, probably 14-16 inches all the way around larger than your light. i hope that makes sense.

so i think that placing them parallel longways would be a "waste" of light, unless you're growing in a long narrow space. if what i've read is correct, placing them far enough apart so that each of their footprints are just touching is the recommended way to use them to maximize coverage and efficiency. so it looks like from your pic what fozzy said is the best way and then use your grow space footprint and work backwards from that to determine the best way of arranging your lights. that will also help you answer the how many plants question. i wish i could find that dang diagram!!

also, i found this from Nebula's tutorial very helpful:

"LED grow lights tend to need a lot of space between the lamp and your plants, which means you need a tall grow space to get the best results. This is actually the main thing holding me back from trying LEDs more. Smaller LED panels should be kept 18" or more away during the second half of the flowering stage to avoid light burning your buds (buds can be burned from too much light even if the temperature is cool), and some of the bigger models need to be kept 30" or more away from the buds. When in doubt, contact the manufacturer!"

that came from the LED section here

http://www.growweedeasy.com/cannabis-grow-lights

i did some testing while i was waiting for my seeds to arrive where i just ran the light in the space and took temp and humidity measurements to get a baseline for when i did get to actually growing. i CANNOT stress enough how right Nebula is about the cooler temperature of LEDs being very misleading. that's unfortunate because the goto rule of thumb that i've read everywhere is if it's too hot on the back of your hand for 30 sec then it's too hot for your plant. that is not gonna work as well with LEDs because they run so cool.

anyway, hope that helps.

[prairie boy]

This is my first grow and it has been quite fun learning about how this all works. I have two 300w Viparspectra lights. Currently I only have one plant going, but am curious what the ideal arrangement of the lights would be. At the moment I have them as you see in photo because it seems to give good coverage. However, wondering if it would be better if I had it so the long sides were parallel.

Also, after this harvest, I plan to plant some autoflowers in 3 gallon pots. I have two questions in anticipation of that grow: 1. How many plants do you think I could reasonably have going with two lights 2. In that scenario what would be the ideal arrangement of the light to give thebest coverage?

Appreciate any and all help!

Derismith88


placement was definitely a concern i had as well when I started my first grow a few weeks back. when i started from seed I put a 300w led about 12 inches or so above them in a 16' x 16' tent. kept them like that for about 3 weeks before i got a bigger tent and moved them. thats when i put 2 - 1000w leds above them. at first they were in a row, but I've had to change them to the pattern they are in in the pics i am attaching. also because of the amount of reflected light near the sides im finding that i am constantly shifting things the girls around to optimize how much light each one gets. as far as height above the plants is concerned I didnt have issues being close with the 300w, but something about how the LED chips are made and how intense each one is on the 1000w unit i did get a some light burning on a few upper leaves before i caught it and moved them up. when i took these pics a few minutes ago i checked my height and its down to 20 inches, which is too close for comfort. they will be getting raised up to 25-30 inches above the top of the tallest plant tomorrow.

and i know where you can find a light spread diagram like bobsakamoto was talking about above. go to ebay and type "1000w LED grow light" in the search bar. click on links until you find one with the diagram. but since you have a name branded product I would look for a manfacturer website and see what they have for spec sheets. in the pics below my tent is 4 x 8 x 6 and im currently in 2 gallon pots. you can see im not using much of that tent at the moment. hope that helps man.