You're in my zone and it really depends upon what you want to plant(as to whether something survives). If you're talking tomatoes and peppers they can't take the weather right now but what they really hate is a lack of light. You can cheat the temperature in a greenhouse but until the days get a little longer plants don't like to grow. All it takes is a little cold spell(always one in the 1st week or 2 of May where I am before Memorial Day and they can be zapped(stunted). Size matters with greenhouses as the cold creeps in and the center stays warmer. In a small greenhouse there is no room for error. I've kept a tomato plant alive outside wrapped up in heavy grow cloth in April but it was old and used to cool weather(attic dormer). Last year I tried to cheat and lost all my tomatoes in a large greenhouse(relatively). It was poorly insulated though. There's no getting past light though. If you do mean warm weather plants they hate April and aren't overly crazy about May.

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

Thanks for all the nice comments, guys. This greenhouse was a long time coming, and I'm thrilled to finally have it up and running. The floor is gravel right now, BTW. I may put something like pavers on top of it later ... and I might not. Craig's List has sites in Atlanta, Athens, Auburn, Brunswick, Columbus, etc., in Georgia. Pick one or two sites that are closest to you, and I bet you'll find users near by who are posting items that you can use. None of the materials I collected were right here in Fredericksburg. I have driven as far as 3 hours to get an item that I wanted -- the antique store doors that I'll use on my workshop building, for example. Most of the action on CL in my area is toward DC and Maryland .. which can be as far as 2 hours away (the skylights were in eastern Md.) I know it's still early in the season, but things are humming along fairly well. The only glitch so far was when the temps got down into the teens on Monday night -- my water line froze solid .. even with the heat tape on it. Fortunately roses can take the cold, so no harm was done ... except for a broken hose fitting. Now I have to make time to get DH out there with me so we can install the pool cover on the beams over head, to lower the ceiling and keep in a little more heat. I can see that hanging out here will help with my winter blues. I love seeing what everyone else is doing in their greenhouses, while everything outside is frozen. Connie

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