Following our recent post on grow mediums, let’s delve into the practical implications of several ongoing studies on grow systems and how they can impact seedling growth. This topic is sure to pique your interest.

We don’t believe in the “our system is better than your system” rhetoric; if you grow, you contribute to a healthier, more sustainable community. With better information, growers can make decisions that reflect their unique operation. As we looked to establish our farm, we spent much time experimenting with different hydroponic systems. We have two systems growing in our testing room: an aeroponics system and a deep water culture (DWC) system. Aeroponics receives much attention, and we were excited to study both the qualitative and quantitative inputs and outputs. DWC is more common among commercial and recreational growers and is highly regarded for its ability to produce fresh produce in a fraction of the time of a field crop. Did NASA miss the moon with the creation of aeroponics, or is the industry over its head with deep water culture?

Here are our first thoughts:

Aeroponics:
The development of aeroponics has significant roots in NASA’s research. In the 1990s, NASA explored aeroponics to grow food in space. They found that aeroponics could significantly reduce the water and nutrients needed, which is critical for long-term space missions with limited resources. This research demonstrated that aeroponics could produce higher yields in a shorter time than traditional soil-based methods, making it an ideal solution for space agriculture and influencing its application on Earth. But how does space farming work on Earth without the support of an engineering team?

Aeroponics offers compelling growth rate data despite its reputation for being expensive to start and sensitive to operate. This data, backed by decades of independently verified research, underscores the practicality of aeroponics as a growing system.

Deep Water Culture (DWC):
Deep Water Culture (DWC) is a hydroponic method of growing plants where the roots are submerged in a nutrient-rich water solution. This technique offers several advantages for plant cultivation. One of the primary benefits is the constant availability of water and nutrients, which promotes rapid and robust plant growth. Since the roots are continually immersed in oxygenated water, plants experience less stress and can absorb nutrients more efficiently.

NASA has also played a significant role in advancing DWC technology. As part of their research into sustainable life support systems for long-term space missions, NASA explored various hydroponic methods, including DWC. Their studies showed that DWC systems could efficiently produce fresh vegetables in space with minimal resource usage.

Both aeroponics and DWC are sustainable methods for cultivating fresh, locally grown produce regardless of the climate or the hostility of the local growing environment. We found the DWC lived up to the ease-of-use hype. With a basic understanding, DWC could be a set-it-and-forget-it system perfect for the hands-off grower. Aeroponics was slightly more involved. It is not difficult, but it does require regular “tinkering.” Being on the farm every day was not a big deal for us. A dedicated grower would not find the additional involvement an obstacle.

The cost of the DWC system was also less involved. We invested less than a couple hundred dollars for our test system of a couple hundred plants. Pumps and aerators are easily accessible at the local hydroponic or pet store, and any other plumbing fixtures can be found at the local hardware store. At this scale, our aeroponic system costs even less. We found a high-pressure pump on sale, and the nozzles were found on Amazon for $20. It’s important to note that aeroponics would be more expensive at larger scales, but the costs have come down significantly.

We have heard that aeroponics has a greater risk of crop failure due to the roots being exposed without access to moisture during a power outage. This seems logical. With the DWC system, the plant roots continue to be submerged in the event of a power outage or pump failure. We created redundancies and a battery backup for our aeroponic system to ensure we don’t lose a test crop during a spring storm. We also built a redundant system for the DWC operation, and I’m sure any commercial grower would do the same regardless of the system they use. This, too, is a non-issue.

On the surface, DWC justifies its dominance within the growing industry. It’s easy to maintain and requires a modest investment to begin. However, although ease of use is necessary, it should not be the most important factor. What about growing efficiency? This is where the similarities end. Our tests confirm what researchers have reported for decades: aeroponics produces more robust, healthier plants in a fraction of the time compared to DWC. Surprisingly, more robust and faster.

Furthermore, the additional time required to maintain and monitor was more than completely offset by the reduction of the growing cycle. We also noted fewer cleaning, water, and nutrient requirements. Although the study is incomplete, the cost per plant will also be dramatically reduced.

Both systems work well. In our case, aeroponics makes sense, and we will be phasing out our DWC system like we did the NFT system before that. We have a small, skilled team, and the slight increase in complexity is not a concern. We would install backups regardless of our system—again, it’s not an issue. Our goal is to establish the most efficient, sustainable farm possible, and until proven otherwise, aeroponics is the solution that best represents our goals.

We do not manufacture, sell, or represent any growing system. If a solution that outperforms our current systems is introduced to us in the future, we will evolve.

Grow the good,
GreenReach

Photo credit: Earhart Laboratories