Every grower tries to maximize their yield and to keep the production cost low. With regards to the cannabis industry, this result can be achieved in many ways, from optimizing climate control to choosing the right strain to grow. But the question still remains: Is there a way to improve a grower’s cultivation without resorting to expensive solutions, which might also be difficult to implement in an existing facility? This is exactly what the RZTO ( Root Zone Temperature Optimization) solution by Roots Sustainable Agricultural Technologies addresses.
“Our system provides optimum temperature for the root zone in order to increase yields and improve growing performance, save money and energy cost and pollution” Noam Dinar, sales manager and agronomist with Roots, explains. “We are focusing on the root zone because the energy for changing the climate for the canopy is much more expensive than for the root zone.”
The importance of the root zone temperature
The root zone temperature is a crucial factor for the healthy growth of the plant. “Root temperature can improve several parameters throughout the plant growth cycle,” Noam says. “For instance, optimal temperature can help with biological activity, with mineral and water uptake, with fighting pathogens and roots diseases. Therefore, plants grow healthier quicker.”
“The changes in the root temperature can affect the yield both in terms of quantity and quality. We found on the latest experiments dramatically increased in the dry matter yield between 40-270% for both root zone cooling and heating.” Noam states.
The biggest change in the root zone temperature can be easily experienced in the United States, especially on the West Coast, according to Noam. “During winter on the West Coast in the United States, the temperature decreases below zero, in this period we supply to the roots optimum temp and saw the big influence on the plant.
On the left – flower from control plant. On the right - heated plant's flower, both sun grown outdoors next to each other in soil from late summer to early fall in Washington State.
Low oxygen percentage
According to Noam, one of the issues that cause damage to the plants is the low oxygen percentage around the root zone. “Our system helps to stabilize the oxygen level around the root zone,” Noam points out. “We know that when you have high or low temperature fluctuations between day and night, the oxygen levels in the root zone is directly affected. Through optimal and stable range temperature, you can provide a higher percentage of oxygen to the roots and ensure optimal biological activities.”
Circulating water into the ground
But how does this system work? “We are dealing with heat exchange,” Noam takes care to explain. “The water circulates in inserted coils down to 10 m inside the ground – because of the fact that 10 m' down, the soil temperature is constant. So, once we are circulating water inside the embedded coils in the soil at depth with a permanent temperature, the water exchanges heat with the sounding ground (charge) and we discharge that stable heat near the roots. During the summer, temperatures at 10 m are cooler than outside, and in the winter the temperatures down there are warmer. That is how, with only a circulation pump we cool roots during the summer and heat them during the winter. At times we use heat pump for extra cooling or heating depending on location and weather characteristics. We are using that energy to keep the temperature of the seedbed at a stable optimal range. It is a closed system; it is not irrigation.”
With regards to the implementation, the system designed by Roots is very easy to implement and to manage, as it is completely automated. “It is an easy implementation,” Noam says. “Of course, we must implement it before the planting, because you cannot put our system inside the rootzone after the planting. You need preparation before the planting, but the implementation is easy. Additionally, the system is completely automated and it gathers data that can help us tell the growers the things that need to be addressed to support them in setting the perfect rootzone temperature.” This element is very important, according to Noam, as it allows ROOTS to follow up on its clients and support them in optimizing their cultivation processes. “We believe in continuous contact, because we want our customers to succeed,” he concludes.