Building a greenhouse from a shipping container and using it as an educational resource in Kyrgyzstan.
The shipping container is a symbol that is synonymous with growth. It is often used to ship plastic parts to China to be assembled, then shipped back as plastic water guns or whatever a dollar can buy at the discount shops. However, here in Central Asia, the shipping container is a resource to be used in any way imaginable. Kyrgyzstan is the furthest country in the world from any ocean port and as such, most of the containers that make it here, stay here. In fact, there are so many containers in the country that our largest bazaar is made almost entirely out of them — two stories tall, multiple kilometers wide, and employing over 50,000 people!
Shipping containers are basically designed to act like giant Lego blocks. In Kyrgyzstan, they are stacked up in all sorts of configurations to build bazaars, houses, or businesses. So it got me thinking: this resource is widely available in Kyrgyzstan, so why not try and see what else we can do with it? The school at which I volunteer was looking to add something to its science department, and since I’m a big permaculture supporter, I suggested we build a greenhouse out of a shipping container.
What follows is the journey that the school has taken to get to the “final” product we have today.
Our first hurdle was to find an appropriate site on our property. As the school is already fairly developed with very little available space, this was not an easy process and we eventually settled for a less than optimal location that only receives sun for three-quarters of the day. There was a small piece of usable land just outside the greenhouse, as well as a place to build a small ‘grow bed’ out of recycled bricks and cement blocks.
The south-facing wall and the west-facing wall of the container were cut out, making sure to leave the corner joist in place to maintain structural integrity. We then poured a cement foundation in front of the south wall, to allow for an angled framework to be welded onto the container. This also allowed us to increase the inside area of the greenhouse, as we back-filled the new inside area with dirt. Once the framework was in place, we added our glass panels to the new south wall and a glass door and window to the west wall.
By this point, we had a fully enclosed space that could reasonably be called a greenhouse. Here is a short video that shows the greenhouse near the beginning of its construction.
Necessity is the mother of invention
As you read, you might reasonably conclude, “all you have is a metal shell with glass windows!” And in the right place, I suppose that would be all you need for a successful greenhouse. However, thanks to its geographical location, Kyrgyzstan has an incredibly wild continental climate. Temperatures can easily hit 45°C in summer and sporadically drop to -30°C in winter. That is a 75°C temperature difference that the plants must be able to tolerate! This creates a difficult growing situation; we have to be able to keep our plants from freezing in winter, yet keep them from withering in summer. So, to grow plants that wouldn’t usually be able to handle such a dramatic continental climate — while also trying not to use large amounts of electricity — we had to mesh multiple small solutions together into one big solution.
To deal with the summer temperatures, we have installed a ventilation system using locally available electric fans (which also have a local use as spare cooling fans for cars). One fan sucks cool air in, while the other blows hot air out. These fans are connected to a temperature control device, typically used in commercial bakery ovens. There is also a small coppice Acacia tree in front of the greenhouse that reduces the amount of sunlight, and thereby heat, that enters the greenhouse. Because it is deciduous, it does not block any sunlight during the winter months. There is also a large layer of mulch that prevents excessive evaporation due to the high temperature during the summer months.
To mitigate the winter temperatures we put up a layer of 5cm Styrofoam insulation on the non-glazed walls and ceiling. That had an immediate effect, but on its own was not sufficient. We found some discarded bricks to build a thermal mass heater that we then painted black, thereby absorbing radiation during the day and releasing it during the sub-zero nights as heat. We also added a large, old bathtub full of water to act as another form of thermal mass. Unfortunately, even after all this, we realized that when you hit -35° C, there just isn’t much you can do to save your plants from the cold short, of using electric heaters (which we might try next winter).
All that being said and done, our students are having a fantastic time doing small projects in the greenhouse, learning permaculture techniques all the while. They have built hanging bottle gardens, wicking beds, been able to grow jalapeños in February while snow is still on the ground outside, and are also in the process of building an aquaponics system.
Even though the growing season was not continuous throughout the whole year, we were definitely able to extend it by two months on both sides of winter. More and more permaculture principles will slowly be incorporated, and eventually we hope to get the growing season to be truly year-round, without having to use supplemental electric heaters. Currently, there is a nice long list of plants that are growing in or around the greenhouse including: oca, Chinese artichoke, sunchoke, Swiss chard, jalapeno, mint, almond, quince, scorzonera, and corn, to name a few.
It is really amazing what can be grown in a small space, in a landlocked country of extreme temperatures, in a metal box, with a little ingenuity and hard work! Who knows, the future might even hold papayas.