There are many facets to growing a healthy crop. Irrigation may be the most important one. Water is obviously critical for virtually every function of plant growth. And too much or too little water can easily stress a plant and make it more susceptible to diseases. The knowledge and experience that growers bring to irrigation practices is key, rather than just guessing what is best for your crop.
“There’s a saying in the industry — your profit is in the hands of the guy who has the hose. We, as humans, have developed technology that can take us to the moon, but irrigation is still controlled by people,” says Dr. Youbin Zheng, Professor in the School of Environmental Sciences at the University of Guelph in Ontario.
More than ever, growers are taking a holistic approach to irrigation. Rather than simply shopping around for the cheapest dripper, they are considering all facets of irrigation that affect plant health.
There’s a saying in the industry — your profit is in the hands of the guy who has the hose.
Holistic Approach to Irrigation
Al Zylstra, Segment Manager for DRAMMWater, says the market is driving growers to be more efficient. With a labor shortage and lower profit margins, growers are looking for any opportunity to optimize their inputs and improve their yield.
“The most significant advancement in irrigation is that the industry is realizing the importance that all aspects of the irrigation system must be designed and engineered together as one system — raw water source quality, storage, treatment, transport pumping and piping, nutrient management, irrigation delivery, controls, and more,” Zylstra says.
The most significant advancement in irrigation is that the industry is realizing the importance that all aspects of the irrigation system must be designed and engineered together as one system
He says key tools used for irrigation, such as vapor-pressure deficit, infrared leaf sensors, and soil moisture sensors, are not necessarily new. What has changed somewhat is that rather than viewing these tools as an optional piece to the puzzle, growers are investing in them to yield the best possible results for their operation.
Zylstra says some of the irrigation methods he sees now are not new, but are more of a twist on existing methods. Changes are coming from the leafy greens sector because these edibles are often in direct contact with the water, leading to even higher water quality standards.
“Leafy greens growers are raising edibles. They have rules to live by that a bedding plant grower doesn’t have to live by,” he says. “We’ve seen the same thing in the cannabis industry. It’s a consumable product and oftentimes, it touches the water. We have to look out for things like E. coli that we never paid much attention to before.”
Integrated Rootzone Management
Growers are likely familiar with the phrase integrated pest management (IPM). Zheng says it is critical for growers to also familiarize themselves with Integrated Rootzone Management (IRM).
“Irrigation is not only an important factor to make sure you can have good plant growth in producing crops, but it’s also related to pathogens and sustainability,” Zheng says. “If you don’t water enough, then you wouldn’t be able to achieve your yield goal. But if you water too much, then you can end up with rootzone oxygen deficiency and hurt your plants. Then you may have to spray, which could damage the environment.”
Zheng says that irrigation is one of the most important management strategies for the success of soilless plant production. It’s a no-brainer that a lack of water would cause drought stress, but too much water also damages the roots. Under oxygen deficiency, the plant is more susceptible to root pathogens like pythium root rot.
The demand for clean water remains very high, and that emphasizes the importance of filtration and water treatment in modern irrigation solutions
“If you want to provide your plants with the best rootzone, you have to take a holistic approach,” Zheng says. “This ranges from choosing growing media to the size and shape of your pots to how you water your plants, depending on the size of the plant, the development stage of the plant, and the environmental conditions. You have to take an IRM approach to be successful in a soilless production system.”
Ricky Elz, Greenhouse Key Account Manager for Netafim USA, says there is a clear trend toward a more holistic approach to water management. Growers are looking for sustainable practices for long-term viability. They are interested in investing more in water quality and a water recycling system.
“Cost effectiveness is crucial, but growers also value the system that promotes water efficiency and reduces waste,” Elz says. “The demand for clean water remains very high, and that emphasizes the importance of filtration and water treatment in modern irrigation solutions.”
By Julie Hullett, Senior Editor, Greenhouse Grower
