The Garden Tower Story, by Colin Cudmore
I've been concerned for years about environmental and sustainability issues. But it was not until my green-thumbed mom dragged me to a lecture at Indiana University by Will Allen that I really woke up to the nature of the food crisis in our world and the ways people are trying to address it. Will Allen and his internationally-known organization, Growing Power, are at the forefront of the fight, and his presentation so inspired me that I knew I had to be a part of the solution.
Soon afterwards in July of 2010, I was volunteering at my local farmers’ market in Bloomington, Indiana. During a break I sat down and watched hundreds of people milling about. One of the vendors closest to me was selling starter plants for gardens. All the time I sat there, not a single person bought a starter plant from him, yet the vendors all around him had a steady supply of customers buying fully-grown, ready-to-eat vegetables. As someone passionate about sustainability and food security, I was surprised and dismayed that people in my community did not seem to be interested in buying plants to start their own gardens. I approached the vendor and asked why he thought people weren’t buying his starter plants. He said, “It’s because people think they don’t know how to do it, or think they don’t have the time.”
That night as I lay in bed, I thought of the numerous reasons that people should start growing their own food, even if they lack experience or time:
- Rising food prices
- Climate change, which is already affecting agriculture around the world
- Continuing economic recession, with growing job insecurity and high levels of unemployment
- Greater prevalence of genetically modified food in grocery stores
- Widespread use of pesticides and herbicides on crops
- Diminishing nutritional value of food due to soil depletion
- Difficulty finding fresh, healthy food in stores (a common problem for residents of inner-city neighborhoods)
Over the coming weeks as I researched these issues, I learned that fully one-quarter of the U.S. population lives in multi-unit structures, most of whom lack access to private land for gardening. Millions more, such as condo owners or house tenants, may have space for a garden, but lack permission to use it. Millions of people couldn’t garden if they wanted to!
I needed to figure out a way to grow a sufficient quantity of food without garden space. A “container gardening system” was an obvious starting point. However, to grow a significant amount of food, most container gardens require a large area. How about a vertically-structured garden instead?
I began researching existing vertical systems. I found that almost all such systems are hydroponic (growing plants in liquid nutrient solutions rather than soil), and therefore require access to outdoor electricity for their pumps and timers. Even worse, they tend to be very expensive. I wanted a solution that did not use pumps, timers, or electricity. I also wanted something that anybody could afford.
Yet I also found that hydroponic systems have their advantages. They grow food considerably faster than traditional or container gardens because plant roots have constant access to nutrient-enriched water. Continuing my research and contemplation of the problems and existing alternatives to traditional and container gardening, I determined that the ultimate gardening system must meet six specific criteria:
- It must be easy and comfortable to use by not requiring digging, weeding, or excessive bending over, as in traditional gardening.
- It must grow a lot of food by having room for literally dozens of plants.
- Water and nutrients must be constantly available to plant roots, so that plants grow fast, as in hydroponic systems.
- It must use floor space efficiently.
- There must be no need for electricity.
- It must be affordable.
In addition to these six main criteria, I also hoped it would:
- Conserve water by keeping moisture loss to a minimum.
- Not require recurring purchases (for fertilizer, etc.).
As the weeks passed, I kept the above criteria in mind day and night. I knew from experience with previous inventions that forcing the creative process didn’t work. One day I found myself purchasing a 50 gallon barrel made from food-grade plastic. I marked the outside of the barrel where I wanted to cut openings for inserting seeds or starter plants. Using a drill, jigsaw, torch, and special jigs I’d created, I made 45 openings, each with a shelf to keep soil from spilling out.
It was a good start, but this first attempt only met three of my six criteria. The majority of openings for plants were above waist level, and I’d filled it with bagged potting soil from a store. (Criteria #1: It must be easy and comfortable to use.) It would allow 45 plants to be grown around the sides, and 5 plants on top, for a total of 50 plants. (Criteria #2: It must grow a lot of food.) It was tall, but not too wide. (Criteria #4: It must use floor space efficiently.)
Researching late at night, I learned about a farmer with 16 world records for growing enormous vegetables who explained that one of his secrets was worm tea (water “steeped” with nutrient-rich worm castings, i.e., worm manure).
If I could combine this nutrient-building strategy in my design, and make those nutrients (as well as water) constantly available to plant roots, I would meet Criteria #3 (plants must grow fast).
Further research led me to vermicomposting, or the use of worms instead of heat to break down compost. If I could find a place for compost within my design, with worms added to it, I would have an answer.
Back at the drawing board, I experienced a eureka moment: I would insert a cylinder in the center of the barrel, which would be kept filled with compost. I cut a plastic tube at a length slightly taller than the height of the barrel, and drilled holes along the sides of the tube, from top to bottom. Next I cut a hole in the bottom of the barrel and placed the tube in it, pushing it out of the bottom of the barrel. After further experimentation I found a way to securely fasten the tube at the top.
I added a plastic cap at the top of the tube, and a removable plug at the bottom. I then cut drain holes in a tight circle on the bottom of the barrel, and placed a container underneath the Tower to capture all of the nutrient-dense water that would drain out (which would be poured back on the top of the Tower at the next watering). Finally, I added legs.
What I was now calling the “vermicompost tube” would allow some of the water poured on top to seep through the holes in the tube, pulling nutrients from both the compost and worm castings into the soil.
As I built the prototype and began testing it, I became increasingly excited. Not only did the design meet Criteria #1 through #4, but also #5 (it wouldn’t require access to outdoor electricity, like hydroponic systems), and #6 (it would not only be affordable to purchase because it was made out of relatively inexpensive materials, but also free to use because the only energy source required was the sun).
I also discovered that it would meet my two extra criteria. The Tower conserved water because it enclosed nearly all of the soil inside, vastly reducing evaporation. Additionally, any excess water would fall into the container underneath and be poured back on top of the tower. No ongoing purchases of fertilizer would be required because the nutrients leaking out of the holes in the vermicompost tube, along with the water that drained from the bottom (a combination of “worm tea” and “compost tea”) would, over time, enrich and fertilize the soil.
I was exhilarated by the Tower’s design. Over the many months of testing since, it has proven itself. The Tower grows a lot of food and grows it much faster than a traditional garden, even while it conserves water. No digging or weeding is necessary. There’s nothing to plug in and nothing to reorder. The Tower is affordable to purchase and free to use. No garden plot is needed, and it uses floor space efficiently, making it the perfect solution for apartment residents, condo owners, and home tenants whose garden space is limited to a deck, patio, or balcony. Finally — and perhaps most amazing of all – the Tower essentially creates its own organic fertilizer, otherwise known as the “black gold” of gardening.
And that is the story of the Original Garden Tower!