Lighting for Cattleyas (How to determine how many FC/Lumens/Watts

[alanbar]

Hi,
I am growing some Cattleyas on two table top lamp stands that have two 24" T5 LED bulbs each .
I can not get the information that I am looking for about which of these light measurements to use.
Thanks, in advance.

alanbar

[raybark]

If you can tell us what you’re trying to accomplish by determining any of that info, maybe we can help more.

Watts, alone, may not be of much value, as that’s the power consumption of the entire lamp, and lamps can have different light-producing efficiency levels.

Lumens tells you the initial light level emitted by the lamp, but as lamp geometry and distance from the plants vary, it tells you nothing about the light hitting the plant. In a T5 fluorescent, for example, the “initial lumens” tells the total output, but the light emitted by the parts of the tube facing upward is lost to a significant degree.

Foot-candles are a measure of light intensity, so is basically “what the plant sees”. A foot-candle is a lumen/square foot. (The metric equivalent, lux, is a lumen/square meter.)