Light bulbs

Leo Martin
Sun, 05 Mar 2017 13:59:58 PST
> ...I will look for a 2' compact
> fluorescent fixture with a single high-output T5 bulb. This is at the
> window over my kitchen sink and I don't like the weird light I have now.
> I did purchase from Amazon a clip on light, I wanted the clip, that has a
> whole lot of small bulbs of different colors, I think red and blue, are
> they LED's? They get the plants to bloom but the color is such that the
> blooms to peoples eyes are not true to their real color, in fact they look
> weird.

I must not have been clear. T5 refers to a particular size of older
technology cylindric fluorescent tubes. I didn't mention what the T numbers
represent because most of the world uses SI measurements. The number after
the T in measuring fluorescent lights refers to the diameter of the
cylinder in eighths of an inch. A T5 is 5/8 inch in diameter; a T8 is 8/8
or 1 inch in diameter. Compact fluorescent lights (CFL) aren't measured by
the diameter of the tube, so anything with a T number is an older
technology fluorescent tube, not a CFL.

There are standard output T5 lights and also high-output T5 lights. People
using them for grow lights use high-output T5s. They are not compact
fluorescent tubes, which is newer technology than T5s. People do look for
6,500 K color temperature with both T5 and CFL. You are unlikely to find
T5HO bulbs at hardware stores, since they are not much used for lighting

Your pink and blue light is an LED light, and was designed in the era when
it was thought the light emitted should be at the chlorophyll maximum
absorption peaks. But this is no longer considered very important. It still
works fine, however. Many people who don't like the look use them in a
growing area away from the main part of the house.

...two LED grow-lights for $50.00 each at a big box store. Still not
> inexpensive. It is the FEIT; model 74302; 2ft LED Plant Grow Light/Blue
> Spectrum Enriched For Vegetative Growth. There is also a model to promote
> blooming. It may be too small for many applications,

To be clear, these pink and blue plant lights are probably not better for
the plants than the much less expensive bright white LED lights sold for
normal lighting use. This size "grow" lamp covers a small area and is very
expensive compared to a standard white LED lamps sold for reading books,
which probably will do almost as well growing plants as the $50 lamp. The 4
foot long LED shop light I mentioned in the earlier message probably covers
more area than this pink/blue 2' light and is around $35.

Leo Martin
Zone 9?
Phoenix Arizona USA

More information about the pbs mailing list