Sorry this may ramble a bit, but so much is going through my little head right now, I'm just letting it out as I think of it. This is bringing up lots of memories of when my dad started out with a small lean-to on the side of the house to sell tomato plants 35 years ago. That business grew several times until we had a single 40 X 50 greenhouse that took up the entire back yard. We now have 5 acres and multiple greenhouses at another location that I have run since 1997 and now produce and sell over 100,000 plants per season. So this is coming from a grower/retailer perspective. Check that you can sell items that aren't grown in your greenhouse. I have to grow 75% of what I sell on site in my zoning. Buy a greenhouse with the appropriate snow load/wind rating for your area. It doesn't take much wet snow to collapse a poorly designed greenhouse. I have two from a Canadian company-Harnois (the third is from a company that I think and hope are now out of business-they were awful to deal with). They were easy to put up and have worked great for us. The last one I bought (30 x 48-which probably the minimum you should consider) was about $7,000 nearly 10 years ago. This price included one heater and three roll up motors and two layers of plastic. I had to build my own end walls to save a little money but you can buy an endwall package separately. You will need electricity for the roll up vents (side and peak) and for the ignition for gas heater(s). But that requirement would be less than for exhaust fans for a ghs with no vents. I wouldn't risk my plants in somebody else's greenhouse that couldn't keep them heated if needed. Nor would I trust my hard work to a greenhouse made from PVC. You need one large enough that people can walk around comfortably and accommodate each vendor. Hoop houses generally don't have a lot of head room along the sides unless you get a high tunnel. If you expect the business to grow get a greenhouse that may be a little larger/wider than you think you need. Otherwise you will be replacing the small one real soon-kind of a waste of money. We went from lots of small greenhouses to a couple larger greenhouses to the single large house and now several large greenhouses. Buy something that is intended to be a greenhouse-you don't want to be jerry rigging something that might not work as expected. There are plenty of professional greenhouse manufacturers (Nexus, Atlas, Jaderloon, Conley, Harnois,etc) out there that will help you. They also will have the proper materials to use and be able to provide you with some guidance. You'll be much happier and the product will probably last a lot longer. Check out Greenhouse auction This is a past auction that still has 450,000 square feet of greenhouse left from a bankrupt nursery. They will arrange shipping for a fee. My hoop houses (20 x 48 & 17 x 48) are open at one end where I can pull the plastic up or lower it to get air and cool off the house. The other end has a regular sized door. The larger one is made so I can pull up the sides about 2 feet off the ground using ropes. Even when fully open, they get 100F + by late May or about 20-30ºF warmer than outside. I use these to hold plants-no customers allowed. Trust me, nobody wants to stay in those conditions for very long-customers or vendors. I also would be leery of the pest issue. Even if everyone has 100% pest free plants (extremely unlikely IMHO) you will get pests. Who will be responsible, and what kind of controls will you use? Preventative or curative? An ornamental grower will have different requirements than an a veggie or herb grower. You may have to have separate greenhouses and spray equipment etc. This idea opens you up to additional liability. If somebody else's plants are lost in your facility you'd better have insurance! Of course you should have insurance if the public will be on your property anyway (a hidden cost and a selling point to potential vendors) $25,000 is not a lot of money. You will run into lots of unexpected costs. Will you have to make other improvements to accommodate the public and vendors-like bathroom facilities? How quickly do you expect to get a return on your money? The people who you should listen to as far as the type of structure are the people who would be using it. What are their needs and concerns? Taking the plastic off in the winter raises a few comments/questions. I assume that you would recover in the late winter/early spring. I don't know about your area but in mine that time of the year is the worst time to try to stretch a huge piece of plastic because most days are breezy. It takes only the slightest breeze to fill a greenhouse cover like a giant sail. You have to do the job when there is no breeze otherwise, you will be miserable trying. It is also a job for several people. The larger the greenhouse the harder it is to cover. Although easier to cover a small greenhouse heats up extremely quickly and has other disadvantages as well. $10 a day is a lot to pay for a vendor-farmers markets in our area cost $50 for the whole season (May thru November, one day per week). Maybe you should charge for the whole season instead of by the day. Or do both but give a discount if they pay for the whole season up front. That gives them an additional incentive to show up everyday. You have to convince your vendors that you have something to offer for their money. And it needs to be something they can't do on their own and will make them money. Find out what they expect and need and then offer that to them. What would the advantage be to have their plants in your greenhouse if they have their own already. Is this advantage worth them paying a little extra money to you? Who will take care of promoting the market? Pay for advertising? Hope this helps!

Last year I started my plants in the portable GH that I used for two years and in the spring I worked on my 10x12 HFGH but did not put it into operation until this year. This gave me a year to play with it before I actually used it. I bought 4 HF vent openers but the operation of them was erratic they would open late or close way too late and the heat was going out the top. Those problems along with the flimsy construction caused me to junk them. For those who have not yet bought vent openers here is something to think about. If you use vent openers they will only work while it is cool when it reaches the 80's you must force ventilate. With operational vents you need to cut you shade cloth if it is not hemmed it will probably tear. Do a search on this forum and read about all the problems people have trying to keep a thermal blanket on in cold weather. If the wind don't tear it off it will get under it and while blowing through under it you have no dead air space. READ NO INSULATING VALUE. In the FAQ under 10x12 HFGH I outlined how I installed my thermal blanket it absolutely will not blow off or let air under it I leave it on year round. If I use shade cloth I don't cut it because the vents are non operational. For what it cost for 4 quality openers like Bayliss I got a exhaust fan rated at 2350 CFM put a speed control on it and a thermostat and set it for what temp you want to maintain. Warm in the winter cool in the summer and none of the hassle of removing the cylinders from the openers every winter no problems with shade cloth or trying to keep thermal blanket on keeps GH at lower temps and no worrying about a wind storm blowing the open vents off while they are open. I'm at the age that I don't want to be putting a pool cover on and off or be out side in the middle of a wind storm trying to save it. I set the thermostat and leave knowing that it will be fine. Only risk is if the electric goes off it won't work but if it is hot and the power fails your roof vents are not going to cool it anyway and when the exhaust fans is on you need the vents closed. I did away with the roof vents and I have no regrets

Can I assume that the reason you are building the greenhouse to to keep the bugs off the tomatoes? WHen I think of green house i think of a structure covered in plastic. Have you considered growing the tomatoes using a row cover to keep the bugs off. The green house (covered in plastic ) will need to have vents to keep it cool in summer. It will get very hot, depending where it is located. Yes 5 gal, food grade buckets will work, Look for instructions on how to make self watering pots - on internet. Maybe make a raised bed, use conduit to form hoops making a cold frame structure and cover with a screen or row cover or something that allows the air to flow.

Hello Marina, The "Old Rose Nursery" has the Canadian hardiness zones for many of the roses he offers. The Canadian hardiness zones differ a bit from the USDA hardiness zones. http://www.oldrosenursery.com/availability.htm I am in the Canadian zone 3b. "John Cabot" has been in itÂs rather shady location for a number of years now and has performed well enough. "Morden Sunrise" is new to me this year. I have been advised that without protection it dies back to the ground each winter. I have been very pleased with itÂs performance so far. I have "Morden Ruby" but am thinking of removing it. The blooms on "Morden Ruby" tend to rot in damp weather. The bush itself has been very vigorous. If you wish to use any of my poor efforts at photography they can be found at the link. Ian Here is a link that might be useful: Roses for Marina