Wow, the book I ordered (
Fresh Culinary Herb Production) came today. I only ordered it Sunday night. It wound up only taking 4 days to process the order and make it to my doorstep. That's quick, and was sent "USPS" mail from Colorado to Arizona.
I called 1-800-stake-it yesterday, and they made the arrangements to have all the utility's come out and mark underground lines. It takes 2 days for all of them to respond, but they'll be done by Friday night. The phone line is the only one I expect to be in the area I will be digging in. They marked it today, and it's exactly where I thought it would be. I wont be able to dig within 2 feet of it on either side. That's fine, that is what I expected anyway. My friend the electrician also tells me it's probably only a foot or so down (FYI).
Also My friend (the electrician) came by yesterday to give me an estimate. I expected 2 breakers to be enough, but he advised me I would want/need 3, because the portable AC (I don't expect to use much), should be on a separate breaker because it will pull about 15 amps, and one breaker wouldn't be enough to run everything else (pumps, fans, propagation
lights). So I'll be getting three 20 amp breakers installed. It will run me about $250 to install the breakers, hook up a junction box below the breaker box, run the wires through the electrical conduit to the greenhouse, and finally wire the the water proof outlet boxes I setup in the greenhouse (with all GFI outlets).
The greenhouse will be attached to the ground by sliding the 2 inch electrical conduit frame into 2 1/2 inch electrical conduit buried in the ground. The same way the metal frame is attached to the ground in the pictures attached. The biggest difference in the in my greenhouse from the one in the pictures (besides the actual size) is I will be using electrical conduit instead of metal fence post tubing. And the doorway will be on the long side, rather than the ends. The base wood framing will be pressure treated wood so it wont rot.
The greenhouse floor will basically be packed dirt. However it will have a couple of layers of weed control screening to keep down soil borne pathogens and pests within the greenhouse. I may also add a layer of crushed rock (
Arizona Decorative Rock), it will take about 2 tons if I do. The gray rock is only $20 a ton, and I will probably order extra when have it delivered for subterranean heating and cooling system back fill (for better drainage of the sub T system).
The reason I'm not going with permanent flooring isn't a property line, or city code issue. It's for my moms sake, I want everything removable. I don't want to take out the greenhouse and leave a ulgy cement patch in the middle of the yard. The property line issue is because of the easement between property that allows the city access to the power line poll. It's not illegal, or even uncommon for people to encroach in that area. But should the city need access to it, and there is no other way, they can tear down anything in their way at will, and without paying to replace it. So if you do build in that area, you build it at your own risk (like my neighbors wall). I just want to avoid those issues, so I wont be building in the easement area. However if I decide to place a in ground reservoir there, I plan to leave space so I can build a solid bridge over it they can drive their trucks over.
I may in the future (money permitting), decide to install pave-stone flooring in the greenhouse (perhaps even around it). But when I expand to another location I will probably go with a decomposed granite (
Stabilized Decomposed Granite and Crushed Stone Stabilizer) or traditional cement flooring. The decomposed granite is supposed to be just about as hard and smooth as cement, but cheaper and nicer looking.
After taking some measurements today above the retaining wall, and considering the 4 foot wide 275 gallon water tanks. It just wouldn't be reasonable to put it just behind the wall. In order to do so it wouldn't be more than 1 foot away from the retaining wall, and thus wouldn't provide enough insulating effect. I am considering farther back behind the wall, as well as between the bushes. That would be about 6 to 8 feet from the wall. The ground is too hard there for me to tap a poll down to get a temp reading. I would need to dig it out by hand, or rent a electric post hole digger. I will try to get some fittings to hook up the hose to PVC tubing, and try to bore out a hole with water pressure. But it's probably going to be to rocky for that to work.
I know from experience here that you don't really start to feel the cool earth until about 18 to 24 inches deep. That's from when I dug the 30 inch deep hole for the
reservoir for my tomato's. Though my concern with ground temps behind the retaining wall are because it's on a hill and I'm not sure how that affects the ground water there. But I have always planed to artificially aid in ground water anyway. I'll be placing soaker hose around the in-ground reservoirs near the surface. Placing it a few inches down, and surrounded by sand to aid in drainage, as well as help keep the soaker hose from becoming clogged from dirt.
Then connecting the soaked hose to a automatic hose timer, and setting it to run for a few minutes at a time, once or twice a day. That will keep the sub soil wet all the time, and give me the maximum geothermal effects without using too much water. I will also keep track of the
nutrient temperatures, both with and without the use of the soaker hose. I want to see just how much effect it actually adds, as well as how much water it needs to get the maximum effects. And I can use that experience and data for a larger scale operation later.