Leading growers and researchers highlight the steps that controlled-environment operations are taking to automate their irrigation practices, and the challenges they are facing.
By Brian Sparks, Senior Editor, Greenhouse Grower
Ornamental growers are consistently looking to manage their water use and obtain better control of their greenhouse environment. The good news is that a good relationship with your supplier can make that process easier. Here’s what two companies have done recently.
Michael’s Greenhouses in Cheshire, CT, is one operation that recently upgraded its irrigation system. Patrick Herzing, General Manager at Michael’s Greenhouses, says the company, no doubt like many others in the industry, was looking to improve on its sustainable use of water by reducing how much of it is wasted.
Herzing says he was able to address three different concerns when upgrading Michael’s boom design:
Inclusion of mist with existing booms in an area for propagation. Herzing worked with Greenhouse Specialists Inc. on the installation of its GTI Boom system, and Dramm, which supplied the mist bar and mist heads.
“This combination gives us better control of both the boom system and Dramm’s Polyrail Fog system,” Herzing says.
Using the booms to spray nematodes and capture hanging baskets as well as the crop below. “With the GTI, we built an additional set of spray booms that run vertically near the top of the boom and can do both with the use of an air bubbler to agitate and a Dosatron injector.” Herzing says.
Making the nozzles on the boom adjustable to target different size containers. “This allowed us to stop step-watering with adjustable distance for the water bar nozzles to reduce waste of water and nutrient feed,” Herzing says.
Michael's Greenhouses improved its sustainable use of water by upgrading its boom design and incorporating technology solutions for multiple production challenges.
Pacific Plug & Liner in Watsonville, CA, made a similar upgrade, but theirs was the expansion of a fogging system.
“We added fog in one of our greenhouses, and after we noticed the benefits, we expanded to at least four full greenhouses in our operation,” says Marlon Carrera, General Manager at Pacific Plug & Liner. “We are working with MicroMist Systems, using two different air compressors to allow the fog to be well distributed in the greenhouses.”
Carrera says the system has helped provide better relative humidity in the greenhouses, which is a big concern in California where the air can be very dry.
“This system allows (the greenhouses) to sustain relative humidity consistently higher than 60% at all times,” says Carrera, who notes how MicroMist Systems guided them in installing the system in the first greenhouse.
“We were able to do the rest ourselves, but we have been receiving support every time we need something from them,” Carrera says. “For example, they told us we needed to treat our water before the fog in order to avoid the nozzles getting clogged due to the rust that water produces.”
Pacific Plug & Liner incorporated fogging technology to create a more stable growing environment in its low humidity California climate.
When it comes to irrigation in controlled-environment plant production, there has certainly been a push toward automation, especially among larger producers. However, successful implementation of emerging irrigation technology still comes down to having a team of well-trained growers.
As manufacturers continue to develop new innovation in water management technology, the research community has also played a key role in helping growers along the way.
Irrigation is one of the most complex tasks greenhouse growers must perform, but it’s also core to producing a high-quality plant, according to Paul Fisher, Ph.D., Professor and Extension Specialist in the Environmental Horticulture Department at the University of Florida’s Institute of Food and Agricultural Sciences.
“The lack of labor today, coupled with employee turnover and industry competition, has made irrigation knowledge a major pressure point for our industry,” Fisher says. “So many factors can affect irrigation decisions, but it still comes down to having a smart, well-trained team of growers.”
Fisher notes that it’s important for these experienced growers to document best practices and develop training programs for new team members.
The crop you’re producing can also play a major role in your irrigation needs, Fisher says.
“Vertical farms and hydroponic operations, for example, already have control over much of their growing environment, and this control usually involves delivery of both water and nutrients through the same line” Fisher says. “For these growers, the bigger issue is being able to maintain their nutrient solution.”
Recycling nutrient solutions in hydroponics and vertical growing is all about maintaining water quality in a way that allows you to keep supplementing extra fertilizer and controlling pathogens, without having to dump any of that nutrient solution, Fisher says.
In the ornamentals industry, there are also more young plant growers seeking a completely controlled environment for plant cuttings.
“Many of these growers are adding technology that provides greater consistency,” Fisher says. “The standard approach is to control vapor pressure deficit (VPD) when propagating cuttings with misting or fogging systems.” This approach, Fisher says, helps better manage the moisture level around the cuttings, including within the growing media.
Of course, the size of the operation still matters, according to Stephanie Burnett, Associate Professor of Horticulture at the University of Maine.
“Bigger growers have access to a wider range of water monitoring tools, which gives them a better idea of their environmental growing conditions,” Burnett says. “The challenge is for small to mid-sized operations who may be looking for similar systems but at a lower cost.”
Burnett notes that there are some cost-efficient water management systems. However, these systems can require a higher learning curve, which has prevented more widespread adoption.
Delivering these tools, Burnett says, could come easier with more partnership between growers, researchers, and suppliers.
“It would be great to see more communities like this develop,” Burnett says. “We’ve seen it with the lighting sector of our industry, and we need more interaction and collaboration like that.”
