Hello,

Looking to ask some questions about best materials for greenhouse sheeting in deserts.

Real issues with poly film I think. Here are the parameters.

High winds of 50 MPH occur seasonally. Gusty, non linear winds that knock stuff silly momentarily, then return to steady blowing.

Extreme heat. 120F is not unheard of.

Extreme sun- to say the least. Very high UV index- feels like you are standing on the sun.

Cold-ish winters. Single digits are not uncommon.

Heavy driving rain the likes of which you have to see to understand. Often combine with high winds.

"Gritty" environment, the wind blows lots of tiny particulate, sort of a mild sandblaster.

Occasional snow to a foot deep.

Occasional hail to pea sized. Rarely bigger.

I did a search for desert greenhouses on this site and came up with zilch. Everything is geared more towards those that are all wet. Still, I doubt I am the only guy who wants to build a dessert greenhouse. (I have this crazy idea of selling natural vegetables to folks in Las Vegas.)

Materials I am looking at: UV resistant acrylic. UV resistant polycarbonate. Something called Solexx. Good old glass. Anything the rest of you can think of!

Obviously cheaper is better, all things being equal.

I need a greenhouse for winter vegetables. I think it should be easy to maintain an above freezing environment, given our bright winters in Arizona. (And I suspect most other deserts.) I would kill for a tomato off the vine in winter!

YLE (Jeff)

I know some folks around here have used Solexx to good effect. We face many of the same issues in Phoenix, except the snow. We are probably less windy than you are up in Kingman too.

I used corrugated fiberglass when I first moved into the desert, about 30 years ago. It lasted 2 summers before cracking into pieces and blowing away.

Keep us posted.

Thanks for that information Juanita. I had thought about using clear fiberglass panels. I use the metal version for roofs on shacks and what not, so was comfortable with how I might attach it. I did wonder how well it would hold up though. Apparently, not too well!

Jeff

consider the underground greenhouse. I am. Everything I've read about it is encouraging, except the humidity problems.

Hey Jeff,

I'm in a similar climate except we never get cold--one thing i'm looking at is a modified walipini with geothermal cooling. Every living thing in my desert goes underground or under shade to survive--it's a pattern that I think bears following.

Neal

Hi Neal,

I hear you there. I use to see exactly the same thing in Kingman. Even the owls go underground in our deserts! I have the cutest picture of nine owlets in a hole my dog dug. There are lots of little heads watching me in the photo. I will see if I can scrounge that pic up.

I was amazed at how deep the soils are out there too. When they were drilling my well, they needed a temporary pool of water. They dug a pit over 10 feet deep and then lined it with plastic. While digging it, we came across several "ant freeways" and several more desert rat transit tubes. I was amazed at how deep they were and how trusting the ants were. The tubes were easy 6 feet deep and many were deeper. The ants just kept falling out of the tube and would crawl out the sides with a question mark look about them. (Maybe they were rear ended by the ants behind them?)

Anyway, my point is that it is amazing just how deep life goes in the desert! And it is amazing how deep the soil goes too. So I think you should be able to work out something with the geothermal mass- should work great. DO keep in touch and let us know how that works out. I am interested in various techniques for heating the green house with passive heat, but want a real world opinion from a fellow desert dweller.

Jeff

I am glad to read your post because I am looking at Arizona and NM as well. It sounds like you are in the northern half? I am looking south to try to avoid some of the weather extremes, especially the cold. From what I have read, I would second the walipini. First reason is to help maintain a stable temperature. The second, if you put in a glass roof - or whatever material - and it is flush to the ground, it will be less affected by high winds and other extreme weather...you would have to make good provision for drainage, for your rain storms, but that should not be too terribly difficult

I noted that this is a very old post, but if someone is still considering a Walipini, there is a nice PDF at this site: http://www.bensoninstitute.org/Publication/Manuals/Walipini.pdf

We use attached greenhouses to heat our houses here in the high desert. We have a cold winter (6 weeks of ice skating, nights min maybe -6F, -21C), and sometimes get very strong winds. In spring sometimes the wind damages a corner of a greenhouse and hastens removal, but usually the wind doesn't cause damage. We buy UV-resistant film intended for vegetable production greenhouses. What I like is that we remove it for the summer so you have a normal house in summer.

I put pictures on another thread: http://www.permies.com/t/21723/greenhouses/Greenhouses-Altitute