How To Build a Greenhouse on the Cheap

Step 1. Find a location that gets plenty of sun. In the northern hemisphere that would be a location where your greenhouse will catch the southerly sun in early spring. Gather about 25 cinder blocks and line them up, nine on each side parallel to each other and 5 or 6 on the end, or 8 ft.

Step 2. Bend the stock panel fence (cattle panel 16’x52”) and rest on the inside of the cinder block. We used small fence posts to drive into the ground through the cinder block and then rested the panel fence on top of the cinder block. This held the fence in place until we could drive longer posts into the ground through the block.














Step 3. Drive fence posts (or heavy gauge re-bar) into the ground through the holes in the cinder block. Use about six posts on each side. Hook the posts through the panel fence to hold it in place. This will allow you to rest the panel fence on top of the block giving you added height (about 6’,5” or more). Use zip ties to tie the panel fence to the fence posts. Don’t hit your partner with the sledge hammer, just hit the posts.

Step 4. Get a door frame and door. We had a couple of old ones that we used. The first one was too tall and too heavy so we took the door off, cut the door frame to fit inside the hoop house, and then cut an old aluminum storm door to fit the frame. We hinged the door inside the frame and then hung the door to the panel fence with zip ties. I swear this is not a zip tie commercial! We then cut out pieces of plywood to fit around the door and at the top of the door and then zip tied them to the door and to the panel fence. I swear this is not a zip tie commercial, but if anyone who makes zip ties wants to sponsor my blog, I won’t object. We also used two short stakes driven into the ground to support the door on each side of the hoop house.










Hmm. Now what’s wrong with this picture?

Step 5. Set the end blocks on the opposite side of the door and then cover the panel with plastic.

Step 5.5. Reassure your wife that you are not turning into “Jethro” from the Beverly Hillbillies. The overalls, hat and the above ground pool kind of suggest otherwise. But the Bono shades add a bit of post-modern eclecticism.














Step 6. We used two 2x8 boards on each side and ran the plastic underneath the outside board and drove long screws from the inside to the outside board pulling them together. The inside board will be about a 1 ft. shorter than the outside board, depending on the size of block you use. We did this again on the other side of the greenhouse and then just rolled the plastic in the boards on the back side. We did not tie down the backside permanently because later in the spring we might need to open it up for ventilation as the temperatures can easily climb to 120 degrees plus when it is only 80 degrees outside. I do plan to get some pink insulation and stuff down in the cinder block holes to help retain some of the warmth at night. I will also insulate around the door with some weather stripping.











Step 7. (optional) Add irrigation by plumbing 2 x ½ inch PVC pipe to the inside top of the structure and place small 1/16th holes in the PVC to create a misting effect. Attach this to your garden hose with a spigot.

Total cost: For us about $120.00 since we already had a lot of the materials or materials were given to us. But, I don’t think it is unreasonable to build one for less than $200.00. Just be good at scrounging around to drive the cost down.