Optimal Artificial Light

Tom21

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I recently started this hobby and after realizing that I needed artificial light went out and got two. One is a full spectrum CFL. The other is a 10xRed and 2xBlue LED grow light. At six inches they put off 100k and 15k lux respectively. I've read that 10k lux is enough to grow my trees (dwarf jade and a willow leaf ficus) but I wanted to make sure that was correct by running it by you guys. What is the optimal light? I have no suitable window to place the trees in either.
 
Sounds good Tom.

Time for some pictures!

Sorce
 
I come from a reef aquarium background so I build my own high powered LED lights. A lot of those grow lights are overpriced with bad led quality. DIY may be to much for most but if your looking for a nice display get a full spectrum reef light-that way it looks good to you as well. If there going in a tent or something then you can buy the red/blue grow lights as the purple light won't be seen.

I'll take a couple picture of my setup and show you what I mean
 
Also be aware that people may scoff at my set up saying its to much but I have been growing corals and mangrove for years with great success. So while may not be required for trees to survive and do ok growth. My approach is is to get full spectrum and have trees thrive and have great growth.
 
I know this question doesn't follow the thread title, but is it too early to repot my ficus? It needs it desperately. It will be an indoor only tree
 
Here is the picture of the newly potted willow leaf. Thinking about doing an informal upright but will continue to think until early March :)
 

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What soil did you use? Kinda looks like potting soil?
 
It's bonsai soil. It looks dark because I had just moistened it up because it dried out a little. It has volcanic rock and river sand as well as some organics. Will it suffice? It is clearly labeled bonsai soil
 
At six inches they put off 100k and 15k lux respectively. I've read that 10k lux is enough to grow my trees (dwarf jade and a willow leaf ficus) but I wanted to make sure that was correct by running it by you guys.

I think you might have your numbers mixed? Tropical sunlight at noon over a reef on a clear day in summer is 30k lumens. A brand new 175 watt metal halide lamp at 12" is 14k lumens. I don't want to even be in the same room as a 100k lumen lamp :) We're talking Michigan Stadium bright.

Oh - I found a 100k lumen lamp! Shield your eyes - at 1000 watts it's plenty bright :) (I'm just messing with you Tom - I'm sure you meant something other than 100k lux) :) Can you imagine the heat this thing puts out at 1000 watts? Here in Southern California, it would cost you $.35 per hour to run that bad boy :)
 
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Yeah... it's possible i did mess up my numbers. I'm using the whitegoods app for iPhone to measure so ill play around with it a little. It is in a reflector so it should stay at a decent level. Regardless of what it really is, is 6-12 inches a good range to aim for?
 
You want it close, but you need to be concerned about shadowing. If it is TOO close you will get weird foliage growth on your tree - heavy growth on top and minimal growth in the middle and bottom because the branches are all shaded. That's one of the reasons why growers use light rails to slowly move their lights around. Reflectors also help because they bounce the light in at an angle and it is less like a spot light.
 
What size lights do you use for starting seeds? I have two that put out enough for 'herbs' according to some websites. I'm going to try growing this years garden seeds (tomatoes, flowers) in them and after they go outside I am trying some tree seeds.
 
Both of my lights are in reflectors so that's good. Thanks for your help
 
I'd avoid that light. It's got a lot of red, not enough blue. The blue is what the trees really use.
 
Do you have a good suggestion? A light with more blue? I've looked but haven't had much luck finding a good one
 
Or, you could just go with a T5 setup. It's hard to find LED lights that aren't made for flowering plants, and those you do find are pricey pricey.
 
Great info in this thread, I'm looking at picking up some COB LEDs I have a question about spectrum, should I be looking at the high blue side of the spectrum, I was thinking closer to the plants response curve the better, these are the spectrums I'm looking at:
I was going to pick 4000K as it has high peaks in both the blue and red spectrum with a high overall spectral intensity. But should I be looking at higher temps for more blue light, in the 5000 - 6500K range?

Cheers,
Connor

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