I don't see it on their website!

A lot depends on how you intend to use it, but if it's the one I saw in our local Costco recently, and having a Harbor Freight model myself, I'd recommend spending just a wee bit more and get the Harbor Freight 6x8 model - $329 regular price, goes on sale a few times a year for $299, and if you sign up for their newletter, you'll get a coupon for either 10 or 20% off (I forget which).

The frame of the Costco model seemed very flimsy, the ventilation inadequate, and the panes, though pretty, seemed very thin and are single-pane, so will not be much good in cold weather and I think be more inclined to overheat quickly in mild temperatures.

The 6x8 HFGH is not difficult to assemble (my oldest son put it together in one day, with a little help from me), has 4mm twinwall polycarbonate panels and, so far, I've found the ventilation provided by the one vent to be adequate. (The GH is in the dappled shade of a deciduous tree, and I open the sliding door on hot days.) With some insulation and a small electric heater this greenhouse was usable all winter long without breaking the bank. What a treat to have fresh tomatoes, lettuce, herbs and peas, as well as flowers, in the dead of winter, and to have such a delightful spot for garden-related puttering or just relaxing.

Just be forewarned that this greenhouse stuff can be addicting ... fortunately, it's generally quite healthy. Whatever your decision, enjoy!

Diane

I think this is not on the Costco website because it's kind of an instore markdown - they've had them for months and they haven't been moving.

I agree with Diane that they're a bit flimsy, and I would not plan to use it during the winter anyway - just for season extension. However, I've seen those pop-up ones with a zip cover for about the same price. I'm trying not to go down the path of getting a "real" greenhouse because I live in a rented house. Maybe I"ll just see if the price comes down a bit more...

Diane,
What type of heater do you use with your HFGH and roughly how much extra did your power bill go up with the heater.
Also, how warm do you keep it in the winter time and did you use a solar pool cover for insulation or someting else.

Any info would be greatly appreciated, still trying to decide between 6x8 HFGH and making one out of sliding glass doors.

I used a DeLonghi 1500 watt convection heater but would have preferred an oil-filled radiant type if I'd been able to get hold of one quickly enough. The convection worked just fine and has a little fan for quick-heating if needed; I just had to be careful to avoid putting plants directly in the path of that fan and be careful not to drop things down through the grate onto the heating element. It provided a nice even, gentle heat. For backup, we have a small Coleman catalytic model that will provide up to 16 hours of heat on a single one-pound propane cylinder.

I wish I could calculate how much the electric bill went up, but the electric company really messed up in 2004-2005, estimating my bills and such, so that winter's usage is no accurate basis for comparison. None of this winter's bills knocked me off my feet when they came in though, and over the course of the entire winter, I don't think it was a huge increase ... certainly worth the enjoyment we all got from the greenhouse. (I'll have to sit down and do what I can with the numbers I have.)

I had intended (wish I knew how to do italics here) just to overwinter a few marginal plants and some annuals, keeping the greenhouse just around 40 or so. The annuals were so happy, though, promting the disease to progress quickly and a revision of plans; I put many houseplants out there, bought some new things I'd never dreamed of trying before, and grew some herbs and a few vegetables in the greenhouse through the winter. This called for a warmer minimum temp of about 50 degrees.

I did use a clear solar pool cover; it was big enough to wrap the entire greenhouse. I also placed 1-inch foam insulation panels along the north wall and north 1/3 of the east and west walls. The polycarbonate panels are edged with foam weatherstripping tape. Frigid temperatures disclosed drafts around the base, so I did a little retrofitting of insulation where I could and will do a proper job some time this summer.

I have no doubt that there are better, more sturdy greenhouses on the market, but the little HFGH certainly took the winter in stride, including winds gusting to over 50 mph. I'd love a larger one, but this one has provided an opportunity, at a low cost, to learn what I personally will want - and not want - in a larger, more expensive structure someday.

You'll probably be investing a good deal of time and effort in a greenhouse made of sliding doors and probably at least as much money as for the HFGH. There are some threads in this forum showing some fine examples; they can be strudy and handsome. If you are truly sure of the dimensions you want/need for the structure that's good ... but it would be a shame if you get it all done and into your first season decide you wish it were bigger, higher, whatever.

I hope all this helps. Good luck with whichever you decide. Please keep us posted and maybe include some photos, especially if you decide to build your own.

Diane