Friday, April 24, 2009

Green Mountain Greenhouse

It only took 7 months for me to write this sentence.

Last fall, my best.husband.ever Dave and I built a simple greenhouse. The challenge was to 1) work the construction into our ridiculously busy lives and 2) get it done before the snow flew (Novemberish 2008).

We live in Vermont, so cold/ice/snow is a major factor in our lives for about half the year. If we missed our Novemberish deadline and let the ground freeze while we lallygagged at our day jobs, we wouldn't be able to build the greenhouse until May.
Actually, I found a bunch of books but the one that mattered was Four Season Harvesting by Joe Blow. Another time I'll rave maniacally about how much I love this book and why; In the meantime, know that that's where I found the basic plan for our project.

I didn't have the physical strength and confidence necessary to construct this puppy on my own, so I batted my eyelashes at best.husband.ever Dave. (This is not a feminist outrage, I swear -- I have carpal tunnel syndrome and I can't grip anything. And Dave can't resist eyelash batting, so my choice was clear, if somewhat philosophically dubious.)

His initial response to my latest fanaticism was: "Eh." As usual. But (and here's how I knew Project Hoophouse was a good idea) a few days later he presented me with a Google SketchUp of the project. You're starting to see what I mean by best.husband .ever, aren't you? Just wait.

One weekend near the end of October we scraped together the time to collect the materials we'd need to build our 16' x 20' hoophouse:

*12 pieces of 20 ft. long rebar
*1 piece of 2 ft. long rebar
*10 pieces of 18' PVC pipe
*some scrap 2' x 4's
*a roll of "clear" construction plastic

We bought the rebar at HomeDepot and the PVC from our local plumbing supply company.

I wish we had some kind of photo or video record of the day we built the ribcage (the structural support), but the only hands on deck that day were me, Dave, and Calvin, and all of us were pressed into construction duty, so we had to forego documenting the hilarity.

The site we picked was immediately to the south of our house. The house itself would act as a windbreak (important) and also we'd get the maximum daylight exposure (important). Sadly, the spot to the immediate south of our house is part of a gravel loop driveway -- not your optimal growing conditions. Not being able to change the rotation of the planet, we decided to sacrifice the driveway loop and go with raised beds in the greenhouse.

Through the magic of geometry (plus the book told us), we knew that the base of the greenhouse was 12 ft. wide. This is largely dictated by the fact that rebar comes easily in 20' lengths. We also knew we needed "ribs" every 2 feet because we get a lot of snow. So we drove some stakes in the ground and wrapped string around them for a site line: 12 ft. wide x 20 ft. long (the length could've been anything we wanted, really), with markers at every 2 ft. along the width.

Construction day: It's cold and slightly breezy. Dave and I start wielding 20' lengths of rebar (light but loooooong) and realize immediately that we must enslave our teenage son, Calvin. After numerous hilarious but COLD fits and starts, we realize that the best configuration is:
* Mark the short (2 ft.) piece of rebar at the 1 ft. line.
* Persons A and C, who both have strong arms, take turns using a sledgehammer to drive the short (2 ft.) piece of rebar into the ground to the 1 ft. mark, angling AWAY from the hoophouse, at the corners and at every 2 ft. marker.
* Person A grabs a 20 ft. length of rebar and jams exactly 1 ft. of it into a corner hole. The rebar is mostly but shakily vertical at this point.
* Person B, who has weak arms, grabs the middle of the wildly wobbly rebar now in the air.
* Person C starts threading the 20' length of rebar through an 18 ft. piece of PVC, with mostly hilarious results. Person B will have to help.
* Person C grabs the loose end of the rebar and jams it into the opposite corner until it's in the ground by a foot.
* It doesn't slide in easily.
* Person B, weak link that she is, tries desperately to pull pvc-sheathed rebar DOWN and TOWARD Person C.
* Person C keeps jamming, possibly with assistance from Person A, whose corner is already secure.
* Eventually we jam the damn rebar 1 ft. into the ground on Person B's side.
* We repeat the same action for each rib, 2 ft. apart.

What with all the jamming of rebar into the ground, the lack of snow/ice/frozen was pretty important, you see.

Then we ran lengths of plastic over the whole thing. There's more about a door on the end, but Dave has to write about that because I had nothing to do with it.