Hello all, quick question.
I'm going to buy a fluorescent grow light for my Ginseng Ficus in my office. What kind of lumens should I be looking for? Above 1,000? I want to optimize growth as much as I can but also stay on the fluorescent side of things as to keep the heat down. My lamp/fixture can hold anything up to 60 watts.
Your advice is greatly appreciated!!!
Matt
PS: A very small amount of northerly window light does hit the plant but it's a good 5 feet away still.
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Gnome
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mosk1640,
Watts is a measure of energy consumed while Lumens is a measure of output. It was recently pointed out that while Lumens may not be the best measure, it is the one we see on packaging.
In his book 'Bonsai in Your Home" by Paul Lesniewicz shows a chart that starts at 800 Lux and goes to 2000 Lux with F. retusa cited to require 1000 Lux
Lux is related to Lumens as a function of the area illuminated. 1000 Lumens dispersed over 1 square meter is 1000 Lux but as the area illuminated increases (the bulb is farther from the plant) the measure of Lux drops off. If the same 1000 Lumens is spread over 2 square meters then Lux drops to 500 and so on. So it is apparent that you should get he plant as close to the light source as possible without causing overheating.
If all of this is confusing why not just get the highest rated bulb your fixture can safely handle?
Norm
Watts is a measure of energy consumed while Lumens is a measure of output. It was recently pointed out that while Lumens may not be the best measure, it is the one we see on packaging.
In his book 'Bonsai in Your Home" by Paul Lesniewicz shows a chart that starts at 800 Lux and goes to 2000 Lux with F. retusa cited to require 1000 Lux
Lux is related to Lumens as a function of the area illuminated. 1000 Lumens dispersed over 1 square meter is 1000 Lux but as the area illuminated increases (the bulb is farther from the plant) the measure of Lux drops off. If the same 1000 Lumens is spread over 2 square meters then Lux drops to 500 and so on. So it is apparent that you should get he plant as close to the light source as possible without causing overheating.
If all of this is confusing why not just get the highest rated bulb your fixture can safely handle?
Norm
Thanks Norm. Yea, right now I have a 13 watt, 970 lumen compact fluorescent on it about 4 inches from the top of the plant. As you pointed out though, I think I am going to upgrade the bulb to a higher lumen output just for added intensity and growth being that the lamp is only on for 8 hours per day.
Thanks as always.
Matt
Thanks as always.
Matt
Hey Matt, I don't know what the rules are at your job for leaving the lights on but if you can you need to get a timer ($10 at Walmart) and let it stay on for about 16 hrs. a day.
From what I've read and learned from the wonderful people hear, 8 hrs a day is not enough. See if you can convince the boss it's a good security measure to have a light on from 7am to 11pm.
Cuda
From what I've read and learned from the wonderful people hear, 8 hrs a day is not enough. See if you can convince the boss it's a good security measure to have a light on from 7am to 11pm.
Cuda
Just wanted to point out that watts, lux, and lumens are all insufficient measures of what makes a particular lamp good (or bad) for photosynthesizing organisms. They truly valuable numbers your looking for are the PAR values. These are probably not going to be easy to come by for your plant (what it requires or gets naturally) or for the lamps you'll buy. PAR is Photosynthetically Available Radiation and is what reef aquarium hobbyists use (or try to) as a guide to provide their corals with the right amount of light. A lot has been written about PAR values of various aquarium lamps and fixtures, mostly by Sanjay Joshi, and this might be something you want to look at.
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alexinoklahoma
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kdodds: you are VERY correct with the PAR...I used to have a dozen+ reef aquaria, and had mega-lighting on most of them as I grew coral frags for trading, etc. I usually used *at least* 1500watts of Metal Halides/VHO fluoro on each tank ($$$) and the PAR's were close to what equator sees 'on average'...got HOT and cooling was a chore, LOL.
Part of the PAR is the 'color temp' of light's output as chlorophyll wants light 'peaks' at certain frequencies - *those* freq's are more important than output in toto, of course. Many 'grow lights' do not put out such freq's and are next to worthless overall, IMO. Check the outputs (!!!)
Alex
Part of the PAR is the 'color temp' of light's output as chlorophyll wants light 'peaks' at certain frequencies - *those* freq's are more important than output in toto, of course. Many 'grow lights' do not put out such freq's and are next to worthless overall, IMO. Check the outputs (!!!)
Alex
Yeah, in technical terms, I'm much more familiar with reefkeeping hardware than with botany hardware. But, I think it is correct to state that, with plants, you want a spectral output more towards the red/yellow/green end (5,500-6,500K) than the blue (10,000-14,000K) predominantly used in reef aquaria. You might actually be able to pick up some inexpensive T5 lighting closeouts at some online aquarium shops. I just picked up a pair of 36" 2x39W lighting fixtures for our 125 gallon fresh water tank. I think I paid $60 each.
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alexinoklahoma
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