Subject: Re: Light Levels in a Greenhouse
From: "Bill Robinson" <roseguy@flash.net>
Organization: Flashnet Communications, http://www.flash.net
Date: Wed, 1 Apr 1998 16:07:04 -0800
Message-ID: <MOD$980401.18115@rec.gardens.ecosystems>
References: <MOD$980401.753@rec.gardens.ecosystems>



Michael Mason wrote in message ...

>Does anyone know what natural light levels are required in a greenhouse.
>I've got 2 layers of UV restistant poly and it seems rather dark.
>
>I'm looking for an answer in lumens, foot/candles, etc.
I believe that the "right" amount of light for a greenhouse will depend
mostly
on the plants you are attempting to grow. If you are going to grow mostly
vegetables, you would need more light than if you were going to grow
tropicals,
etc.

At one time, I was interested in growing different kinds of orchids in a
shade
house. I tried looking up the light requirements in the books - also looking
for
an answer in lumens - and got nowhere. I then took my camera with a built
in light meter to a commercial greenhouse that specialized in growing
orchids-
got permission and then messed around changing the settings for the film
speed untill I got the right exposure at f 8. I then went home and spaced
the overhead laths until I also got a reading of f 8 in my shade house. It
worked very well.

If you have access to a local greenhouse that is O.K. for the same kinds of
plants as the ones you are trying to grow, you might ask if you could get
some light readings and duplicate the light.

Bill