fluorescent lights and seed starting

 How close do fluorescent lights have to be to indoor propagation trays to
be effective?  I would like to use the ceiling lights I have in the
basement.  If I were to set up a couple of sawhorses with propagation
mats, do you think I could get by with the ceiling lights, or will I have
to lower them to within a foot or so of the seeds?

 @yahoo.com:


Everything I've seen says you should put them really close like within
inches, but my pet theory is you can build a hugh reflector (or two) from
leftover AOL discs and just use the ceiling light.

 On Sun, 18 Jan 2004 17:58:43 +0000, Salty Thumb wrote:


That's what I thought. Now, if only I can remember where I put that bag of
AOL CD's!

 

    Regular fluorescent lights need to be within a couple of
inches of most plants you might start. say, tomatoes. I'd give them 12
or 14 hours a day too. If they don't get enough light they'll get tall
reaching for the light but be very weak and skinny. Another problem
you'll run into is that as the plants grow taller and you raise the
light to give them room the lower part of the plant won't get enough
light, so you don't want them growing too tall under the fluorescent.
It's best to transfer them to a cold frame and sunlight as soon as you
can.  Plants started under fluorescent must be hardened off carefully
when placed outside or the shock of sunlight will do them in. I've
started thousands of them this way but I'm now very happy to have a
metal halide light. It can be placed well above them and still get
plenty of light to the whole plant. It also allows for a very brief
hardening off period without even messing with a cold frame.

 

I will vary depending on what you are growing.  I have a flat of
parsley seeds germinating under fluorescent lights.  The tubes are
about 2" from the soil surface.  Hang your lights on chains for ease
of adjustment--much easier than trying to adjust the pots and trays.