bonsaiTALK Community - View Single Post - Can flourescent lights Burn?

Rob, methinks you have answered your own question, although I sense that you are trying to confirm your suspicion that the lights caused the damage.

The answer is probably so. While fluorescent lights are much more efficient than incandescent, and therefore emit less of their energy as heat, they still give off some heat proportional to the energy they use. So a lower wattage bulb will generate less heat, and a higher wattage one more. jjeter's bulbs apparently do not get warm enough to have much effect. I have had high output CFLs burn new shoots that touched them in a matter of minutes.

Another way that they can burn is just with sheer intensity, similar to the way the sun scorches leaves outdoors. I have one ficus under my 6-bulb T5 fixture that gets scorch every once in a while in the top of the canopy. There, at only a few inches away, the light is much more intense than lower down where the other plants are.

I would say that in general you don't want your plants touching the bulbs, or getting too close to them. Fluorescent allows you to position lights much closer to your plants, but still not too close.

7-Feb-2008	#3
ckesselring bonsaiTALK Journeyman Join Date: May-2007 Location: Salt Lake City Country: USA Posts: 23	Rob, methinks you have answered your own question, although I sense that you are trying to confirm your suspicion that the lights caused the damage. The answer is probably so. While fluorescent lights are much more efficient than incandescent, and therefore emit less of their energy as heat, they still give off some heat proportional to the energy they use. So a lower wattage bulb will generate less heat, and a higher wattage one more. jjeter's bulbs apparently do not get warm enough to have much effect. I have had high output CFLs burn new shoots that touched them in a matter of minutes. Another way that they can burn is just with sheer intensity, similar to the way the sun scorches leaves outdoors. I have one ficus under my 6-bulb T5 fixture that gets scorch every once in a while in the top of the canopy. There, at only a few inches away, the light is much more intense than lower down where the other plants are. I would say that in general you don't want your plants touching the bulbs, or getting too close to them. Fluorescent allows you to position lights much closer to your plants, but still not too close. __________________ Christian Kesselring Salt Lake City, UT - Zone 7a Member, Bonsai Society of Utah