Efficient greenhouse irrigation systems are the foundation of productive, profitable growing operations. At Harnois Greenhouses, we design and supply advanced water management solutions, from precision drip irrigation to fully automated fertigation controllers, tailored to the specific needs of commercial growers across North America. Whether you operate a high tunnel greenhouse, a gutter-connected poly structure, or a Venlo glass greenhouse, our irrigation equipment integrates seamlessly with your growing environment to maximize yield and minimize resource waste.
Why Water Management Defines Greenhouse Profitability
Water is the single most critical input in any greenhouse operation. Under- or over-irrigation causes root stress, nutrient imbalances, and crop losses, all of which directly impact your bottom line. According to the Food and Agriculture Organization of the United Nations (FAO), agriculture accounts for approximately 70% of global freshwater withdrawals, making efficient on-farm water use a competitive advantage as much as an environmental responsibility.
Harnois systems are engineered to deliver the right amount of water and nutrients at the right time, reducing runoff, lowering input costs, and supporting consistent crop quality throughout the season. Our water management equipment pairs with Harnois greenhouse structures from the planning stage, ensuring full compatibility and simplified installation.
Our Greenhouse Water Management Systems
Drip Irrigation for Greenhouses
Drip irrigation is the industry standard for row crops, potted plants, and substrate-grown produce in commercial greenhouses. Our drip systems deliver water and soluble nutrients directly to the root zone, reducing evaporation losses and limiting leaf wetness that promotes fungal disease. Drip lines are available in a range of emitter spacings and flow rates to match your crop density and substrate type. Compatible with both Dosatron injectors and direct-inject controllers, our drip systems adapt to operations ranging from 0.5 hectares to multi-block facilities exceeding 10 hectares. Learn more about our turnkey greenhouse solutions that include full irrigation design and commissioning.
Fertigation Systems
Fertigation, the precise delivery of dissolved fertilizers through the irrigation line, is one of the most efficient methods of nutrient management available to commercial growers. Harnois partners with leading equipment suppliers to offer fully integrated fertigation units with automated EC and pH monitoring, proportional dosing, and remote management capability. Properly calibrated fertigation reduces fertilizer use by up to 30% compared to broadcast application, while improving crop uniformity and growth rates. Explore how fertigation fits into a complete commercial greenhouse equipment setup.
Greenhouse Water Treatment
Plant health starts with water quality. Pathogens, bicarbonates, heavy metals, and excessive salts in source water can inhibit nutrient uptake and spread disease through recirculating systems. Our water treatment solutions include UV disinfection units, sand and disc filtration, reverse osmosis systems, and pH/EC correction equipment. Clean, balanced water reduces crop losses from root diseases such as Pythium and Fusarium, and extends the service life of your drip emitters and injectors. The Vermax glass greenhouse, Harnois’ most advanced structure, incorporates a revolutionary circular water treatment system that achieves zero wastewater after startup, a benchmark for sustainable greenhouse agriculture.
Irrigation Booms
Irrigation booms are the preferred solution for propagation benches, plug trays, and flat-grown crops where uniform overhead coverage is essential. Our overhead boom systems travel the length of the greenhouse bay, delivering precise, consistent droplet distribution across the entire growing surface. Automated boom irrigation reduces labor requirements significantly and ensures uniform germination rates in propagation operations.
Flood Benches and Floor Irrigation
Flood bench (ebb-and-flow) systems allow water and nutrients to flood the growing surface from below, then drain and recirculate, delivering exceptional uniformity while recovering unused solution. Flood bench irrigation is especially effective for potted ornamentals, herbs, and bedding plants. Combined with our recirculating irrigation options, flood benches contribute to closed-loop water management that dramatically reduces both water consumption and fertilizer discharge into the environment.
Water Treatement
Drip Irrigation
Fertigation
Irrigation Booms
Flood Benches
A Complete, Integrated Approach to Greenhouse Water Management
Harnois is one of the only greenhouse suppliers in North America to offer both the structure and the complete equipment package under a single project team. Our agronomists and project managers work with you from the initial design phase to ensure your irrigation layout, water source, and crop requirements are fully aligned before installation begins.
This integrated approach eliminates costly retrofits, reduces commissioning time, and gives growers a single point of accountability from design through to harvest. Whether you are building a new facility or upgrading an existing operation, Harnois brings the expertise to match the right irrigation technology to your crop, climate, and production goals.
For growers interested in sustainable production, our recirculating and closed-loop systems support compliance with increasingly strict nutrient discharge regulations across Canada and the United States. The University of Guelph’s Controlled Environment Systems Research Facility identifies closed-loop irrigation as a key pillar of economically viable and environmentally responsible greenhouse production, a standard our systems are engineered to meet.