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greenhouse on raised perimeter

Hi all,
New to this group and did a quick search, but did not find this topic in particular. I've been growing organically for over 30 years, owned a few farms as well, but have never had a green house. I am now living in an urban setting in Oregon USA and would like to have a small greenhouse to go with my 9 4x10ft raised cedar beds. I have a great space that will accommodate a 8x12 foot greenhouse. My idea is to build two raised beds (probably 30"x12') with a center aisle, with a 4' bed across the back. What I would like to do is have beds that are about 30" high (made from 2x12 cedar) and utilize the beds as the perimeter walls. I'd like to purchase a kit greenhouse to set on top of the perimeter bed walls, which would raise the overall height of the green house. The height of the beds would depend somewhat on the greenhouse I am setting on them.

The challenge I am finding is that most kit greenhouses are set on a metal base that runs the entire perimeter, including the door. I would need to lower the door to account for the raised perimeter foundation and am looking for a kit greenhouse that would work for that purpose without having to build the whole greenhouse from scratch. I'm sure I'm not the first to think of this, but an online search has not produced kits that I could use in this way without doing some cutting on the kit foundation. wondering if anyone knows of kit greenhouse that does not have a threshold that is incorporated into the greenhouse base?

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Location: Zone 6, NJ (3/M)4/E ~ 10/M(11/B)

OK — my immediate thought was why not just make it a sunken greenhouse... then I was thinking Oregon... do you get too much rain?

This is just one example I quickly pulled from the net. But obviously there are other examples. I’m thinking not quite as deep as the example. Basically, the greenhouse would sit on the ground level, and your path would step down so you still have sort of raised beds, but the subterranean configuration is supposed to moderate the temperature extremes, I believe?


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Super Green Thumb
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Why not build a conventional - ground level greenhouse with boxes inside? Line your walkway with commercial grade landscape cloth then top with road gravel. Helps with the drainage.

Good luck.

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Joined: Mon Nov 06, 2017 5:06 pm

Hi guys,
Thanks for responding.

I have pretty much already decided, for a variety of reasons, that I want to have the greenhouse on a raised perimeter, so not really looking for suggestions on other ways of doing greenhouses. The dug out GH is interesting, but won't really work in my backyard because of pipes. The truth is, I do not really want a dug out GH either.
I'm tall (6'5"), and I also am going to be growing indeterminate tomatoes as one of the crops and they can get pretty tall, so I am looking for ways to make taller sidewalls and a taller greenhouse overall, a perimeter foundation looks good to me.
As noted in my original post, I think I can get away with buying a fairly inexpensive <$1000 8x12 kit and mounting it on top of a perimeter foundation. The only real challenge I see to doing that is the door. It seems most reasonable to lower the door to ground level and fill in the space it leaves with similar twin wall polycarbonate, the only impediment I see to doing the though is the perimeter base that comes with GH kits runs under the door as well, so that would have to be cut out if I used a kit. Was mostly wondering if anyone knew of a kit GH that didn't have the base running under the door. :-)

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Location: Stroudsburg, PA - Zone 6a

I would not suggest building the greenhouse up and using the outside of your raised gardens as the lower part of the greenhouse wall. Unless you insulate the inside or outside of the raised gardens on the side facing out, you are going to have some mighty cold soil in those raised gardens when the weather is cold. You would be much better off building a separate perimeter wall and keeping the raised beds inside the greenhouse. As far as the door, cut the frame there, secure it well where you cut it, creatively figure out how to build a lower extension onto the door that comes with your greenhouse, or dump that door and create your own.

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