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Re: Propogating from Seed

>Over the past few years in the spring, I start both perennials and
>annuals from seed under florescent lights.
>
>It is my understanding (I'm a beginner, so correct me if I'm wrong) that
>most perennials and annuals would grow better and bloom sooner from seed
>if started in a greenhouse, because florescents do not mimic the full
>spectrum of light from the sun.
>
>Here is my question (finally, you say!):  is there any way to use
>florescents more successfully - increasing the "spectrum" by either
>adding different kind(s) of lighting, or by combining different types of
>florescent light bulbs?  I don't know much about florescent light bulbs,
>but I've heard them called "cool light" which I assume means they have
>more of the blue spectrum.  I have also been told not to bother spending
>the extra money on specific "grow light" bulbs, but it seems to me that
>someone in the industry must have come up with a grow light bulb that
>provides a broader spectrum of light.
>
>What's the scoop here, gang?  Please share your thoughts and
>experiences. I am teetering on the edge of going the greenhouse route to
>get better results, but would prefer to stick with florescents as I have
>heavily invested in this process.  HELP!
>
>Heather in Markham, Ontario, Canada
>Cda Zone 6 / USDA Zone 5

Dear Heather,
The difference in growth between real sunlight (like in a greenhouse) and
flourescents is not the spectrum, but rather the quantity of light the
plants receive.  Sunlight just has so many more lumens than any artificial
light source.

It's a complicated subject, but other factors involved are also duration of
light (how many hours), as well as temperatures.  The easy answer is that a
greenhouse, with it's natural  daylight, will , initially, produce
sturdier, better plants as long as it's kept cool enough during the day not
to cook the plants (fairly easy in the winter and early spring), as well as
warm enough (not as easy, and certainly more expensive than flourescents)
during cold winter days and nights.

There are lighting options other than flourescents, like 'vapor lights' (so
popular in the marijuana growing circuit).  These produce more lumens that
common flourescents without the heat associated with other light sources,
but still not as strong as the sun.

Being bad at geography, we are not sure how far north you are, but there
might not be a lot of daylight (for growing things in a greenhouse), in
your area in the winter, as well.

Finally, the difference should be minimal between greenhouse/daylight grown
plants and artificially lit/raised ones.  We very successfully, easily
raise over 1000 seedlings in our little (400 sq. ft.) apt, here in New York
City, for planting out in Connecticut (where the garden is) every year.
Well...if the truth be known...It *does* get a little hard to walk around
the apartment in the spring.  :- )

The biggest 'trick' we found beyond lighting the plants, with regular old
flourescent lights, 14 hrs./day (we use a timer), was keeping them cool.
This prevents a lot spindly soft growth.

As far as the flowering sooner:  This is more true for annuals than
perennials, however again, it has less to do with the spectrum of light,
than *when* the plants are started .

Oh....and you need to keep your plants no more than 2 inches from the
flourescent tubes to get good results.  (Which sort of says something about
the power of that light vs. the sun!)

Bill & Harvey
SKID   Zone 6  CT  USA
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