So i can't decide where i want to permanently place a 50' greenhouse in my backyard. We grow year round in a 30' natural gas heated mist cooled aeroponics light dep self designed Solexx covered hoop structure currently, but it's not optimally oriented or designed for year round growing. Mostly because it runs North to South on the dark green patch (astroturf) in the below image. I had my reasons for placing it there to begin with, like the gravel bed under the nice to walk on fake grass, but you live and you learn.
Note in the first image link below there is a ground cellar entrance at the start of the 57' line. Concrete steps go down about 15' to a shipping container buried underground, the back of which ends just before the line ends at the wall. I live in Zone 9. Summer is hot, the ground cellar being tempered i could use it like an earth battery. Covering the ground over the buried shipping container i assume would only help keep it cool it down there.
Downside is the trees that cast a shadow during fall and winter. The above image was probably taken in March or September. You can see the wall and tree shadow creeping South. It's possible to build over the ground cellar while avoiding the wall shadow, but not the shadow of the palm trees.
This is a shot looking South at the trees. http://imgur.com/a/nZyih That's just a ground cellar entrance cover to keep dust out, not an operational greenhouse, but it's right where the line in drawn in the above image, and where im thinking if building a 50 footer.
Is incorporating the ground cellar worth the added shade? Or should I head North in my backyard about 50' to avoid shade and forgo the greenhouse bomb shelter combo?
You buried a shipping container 15ft underground? Must have been a hell of an excavation! I think a lot depends of what you want to grow. Looks like Cali/Southwest climate which is almost year round as it is. I'm in 9b and can harvest stuff year round in Nor Cal. You can put frost fabric over garden beds on nights where frost threatens. You can use the same frost fabric to shade the sun in summer if needed.
I believe if a greenhouse is oriented running east toe west it should have a solid north wall. Therefore the ideal location would be along the north wall of the yard unless there is a problem with setback or easement restrictions. This also allows you full control over what may shade the greenhouse so that it optimises low sun in the winter and reduces high sun in the summer.