DIY

Autumn’s Inexpensive DIY Greenhouse

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Autumn completed her greenhouse in three days for under $150
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Autumn and her dad finished the 2-by-4 frame with low cost fence boards.
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Autumn was able to salvage her neighbors old windows.
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Curtain cloths provide shade and help to regulate the temperature inside during the hotter parts of the day.
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A vent allows for hot air that rises to escape.
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Water filled containers help regulate temperature swings.
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Water can also be stored to use later.

I live on a small urban plot in the heart of downtown Reno, Nevada. Even though I live within walking distance of a grocery store, I pride myself in growing fresh food for my family. Winter has always been my most challenging growing season, but now I grow an abundance of fresh salad greens in an unheated greenhouse, and I’d like to share my story with you.

My greenhouse journey began with patience. I knew glazing would be the most expensive part of my project, so I made a decision to wait for free windows. One day, I was talking to a neighbor who told me she was replacing her original 1953 single-pane windows, and I found myself blurting out, “Can I have your old ones?” She happily brought them over, and with those beautiful old windows stacked nicely on the side of my house, I began to formulate a plan.

The Important Features

Location was very important. My greenhouse had to have southern exposure and be within a few feet of my back door. This narrowed the location down to a small corner of my patio, which determined the size of my greenhouse; it would be 6 feet square.

Having a beautiful structure was important to me as well, not only because I like being surrounded by beauty, but because my neighbors would see it over the fence, and I didn’t want them complaining.

Also, I wanted a completely off-grid structure that wouldn’t require any further investment to grow food. And lastly, it had to be inexpensive; I had a budget of $150.

With size, location, and budget established, I sketched out my plan and recruited my builder — good ol’ Dad! I’m sure he thought his job was done when I got married and left home, but no, he’s still my No. 1 building partner! I watch everything he does and ask a lot of questions. With every project, my skill set increases, and this was the biggest one we tackled together.

The Build Process

Day one consisted of framing. Within three hours, my dad and I had the 2-by-4 frame up, and I installed the clear, corrugated polycarbonate roof panels.

On day two, I set the windows in place and attached the siding, which consisted of inexpensive fence boards. I used fence boards for the shelves as well — they’re the perfect depth for potted plants.

On day three, I whitewashed everything inside the small greenhouse so it would reflect as much light back onto the plants as possible. I bought “Oops Paint” from Home Depot for $5 a gallon. I was able to complete my little greenhouse in three days, and I stayed within my budget. This truly felt like a dream!

My excitement quickly dissipated after I realized the temperature swings inside the greenhouse were going to be unbearable for my plants. During the day, it would reach over 120 degrees Fahrenheit, and at night, it would plummet to 50 degrees. But I wasn’t about to give up. I set out on a quest to solve my temperature-swing problem. I was successful, and this is how I did it:

Shade cloth. Someone told me that shade cloth could help bring down the high temperatures inside the greenhouse, so I hung some old white curtains across the roof, shaving off 10 degrees almost immediately. That was progress, but it was still too hot to grow anything.

Venting. Because hot air rises, I knew I could add a vent at the highest point of my greenhouse to create a natural pathway for all the built-up hot air to escape. So, I removed a third of the back wall at the highest point and made a hinged panel I could open and close as needed. With the vent and greenhouse door open, there’s a nice cross breeze, but it still wasn’t habitable for plants. My search continued.

Thermal mass. An engineer friend suggested thermal mass as an off-grid solution for temperature swings. Explained simply, I could use a mass of something, such as stone or water, to absorb heat during the day and release it at night (see “Add Thermal Mass to Your Off-Grid Greenhouse” for more information). I decided to use water as the mass, which meant I needed to squeeze as much water as I could into this tiny greenhouse. I went to a local bread store and bought their used 5-gallon buckets with lids for $1.50 each. I filled seven of them with water and placed them around the inside perimeter. The next day, I was shocked; the temperature didn’t exceed 90 degrees during the day and didn’t fall below 70 degrees at night. This slow and even absorption and release of heat was exactly what I needed to smooth out the temperature swings. And best of all, I didn’t need electricity to do it.

A Small Compromise

I soon realized that hauling water to and from the greenhouse was inconvenient, so I added a 15-gallon rain barrel to catch the runoff from the greenhouse roof. I installed a hose spigot at the bottom and placed the barrel up on cinder blocks so I could put a watering can under it. I broke my rule about no electricity in my greenhouse by wrapping a 6-foot length of pipe-heating cable around the rain barrel to keep it from freezing. Frost-free water all winter for $20 was definitely worth it!

This experience has turned out to be such a beautiful lesson in self-sufficiency for my entire family. I hope you’ve enjoyed reading about my journey. Sharing our stories is key to us finding success, and that’s what I love most about this magazine; it features real people sharing real stories to encourage and inspire us all. I love my beautiful, little green retreat in the heart of the city and wish you a winter of healthful greens!