greenhouse DIY greenhouse ideas

I'm living in an apartment right now and would like to build a small enclosure to try to overwinter some plants. The picture below is the area I would like to try it, it's 6-7 feet tall at the top. I'm thinking simple, black tarp along the back and ground for some added warmth (I'm in Oakland, CA so it will rarely, if ever frost here). The wall faces south, and with some 2x4's, a couple shelves, and some plastic sheeting I should be in business.

Any tips on materials, design, layout, best way to ensure some ventilation but maintain warmth, access ideas, etc.? Since it an apartment building I would like to be as delicate as possible, as in not putting holes in the building with screws or nails if possible.

Number of plants isn't all that important as long as I can keep a handful (5-6 would be great, the more the merrier).

image.jpeg
 
Gorizza said:
Something like this would probably work well https://www.themine.com/lawn-accessories/nuvue-2404-pop-up-greenhouse-trade-_12669938.html
24040-pop-up-greenhouse-cover-22-inch.jpg

 
They probably sell them at Oakland Garden Supply.
 
On another note, I might be moving to oakland for some work in SF in a couple months, so excited that overwintering outdoors is a possibility.
Very cool! It was going for a little taller and narrower but this gives me a whole new range of ideas to look into, thank you!

And Oakland is awesome. PM me when you get to town and we can grab a beer. Cheers!
 
Cold frames are popular especial if you have compost at the bottom, its heats things up. Whats also catching on is pvc pip poly tunnels, they just dont need to be big and tunnely.
make the frame and can be weighed down inside with soil.
 
https://youtu.be/i5Zn0nYTGHY
 
I wish I could live in a greenhouse.... except for the heat and humidity.... what ?
 
I built a hoop this season. It started as PVC piping and the "clear" 6mil plastic sheeting from (big box). It worked really well to grow tomatoes and peppers. Plenty of light penetrated to grow things inside. It wasn't intended to be a cold frame though.
 
Peppers and other plants can tolerate (not thrive) in cool temps. They will stay alive if that is your plan. But in a greenhouse or other like structure, even in the cool off-season of California, you'll have to watch the swings in temperature. If you don't vent during the sunny days, a closed greenhouse will get to temperatures that could harm, or even murder your plants !!
 
Then there is the night time !  As the temperatures drop during the night, if the greenhouse isn't vented, there is a possibility that the relative humidity will go way way up, and you'll end up with water condensate of the plastic, which could possibly lead to mold an mildew... 
 
All that fun aside, I think you have a great idea. I'd like to have the workable temps that you have in northern California.  Your greenhouse will be like a child.... you'll have to watch over it often, and adjust things as needed.
 
Good luck to you and Happy Growing !
 
Jeff
 
MNXR250R said:
I wish I could live in a greenhouse.... except for the heat and humidity.... what ?
 
I built a hoop this season. It started as PVC piping and the "clear" 6mil plastic sheeting from (big box). It worked really well to grow tomatoes and peppers. Plenty of light penetrated to grow things inside. It wasn't intended to be a cold frame though.
 
Peppers and other plants can tolerate (not thrive) in cool temps. They will stay alive if that is your plan. But in a greenhouse or other like structure, even in the cool off-season of California, you'll have to watch the swings in temperature. If you don't vent during the sunny days, a closed greenhouse will get to temperatures that could harm, or even murder your plants !!
 
Then there is the night time !  As the temperatures drop during the night, if the greenhouse isn't vented, there is a possibility that the relative humidity will go way way up, and you'll end up with water condensate of the plastic, which could possibly lead to mold an mildew... 
 
All that fun aside, I think you have a great idea. I'd like to have the workable temps that you have in northern California.  Your greenhouse will be like a child.... you'll have to watch over it often, and adjust things as needed.
 
Good luck to you and Happy Growing !
 
Jeff
So the idea has evolved a bit, after doing some research I came across some info about temp swings and needing ventilation. Apparently even in a 50 degree partly sunny day the plants can cook in a cold frame. They make these automatic pistons that have a temperature sensitive wax in them (the wax expands when warm and opens the piston), and these can be set to open between 55 and 75 degrees. They are available on Amazon.

Cold frames I think will be too short for peppers, but I have the idea to build a box 3' deep X 6' wide X 8" high (attached to a plywood base for stability and added weight, since I don't want this thing to blow off the roof and kill someone on the ground below), and build a poly low tunnel that is attached to the frame via hinges, and install one of the auto pistons. The hoop will provide height more appropriate for peppers and I should have enough room for some small planters of lettuce and other greens inside it.

I may insulate with hay and/or add jugs of water to help keep the temps higher overnight, but that may be overkill... Once the structure is built I can add that if needed.

Here in NorCal I have another month before it needs to be completed so it may continue to evolve, and I'll knock it out over an upcoming weekend.
 
the wax pistons work great . I have 2 rv style roof vents as high as possible on the back wall of my greenhouse (12x16x8 tall) . these and a fan keep it right until the outside temps get into the 90's .I do use a couple milkhouse heaters with thermostats in the winter.
 
Back
Top