Featured Agricultural Systems Impactsd

Managing Irrigation in Greenhouses and Nurseries

Most greenhouse and nursery crops rely on irrigation, but drought, pollution, competition for water resources and concerns about environmental impacts are making it necessary for greenhouses and nurseries to better manage water use. Researchers and Extension specialists from 21 land-grant universities are leading a multistate research project to develop innovative tools and strategies that help ornamental crop growers conserve water, minimize impacts on the environment and sustain production. 

The group’s research on the water requirements of plants and the effects of different growing media, container types and environmental conditions has led to recommendations for more efficient irrigation timing and amounts. A newly developed, free mobile app (GroZoneTracker.com) helps growers record, track and share information, making it easier to quickly fine-tune irrigation practices. Growers who used a new wireless soil moisture sensor system reported shorter production cycles, less disease, better plant quality and large water savings. One user reduced irrigation by 50%, saving 43 million gallons of water and reducing water pumping costs by $6,500. Michigan’s largest nursery expects to reduce irrigation applications by 20% and save 50 million gallons of water. Preventing overwatering will also help them cut fertilizer applications by an estimated 10%, which would send approximately 22.3 fewer pounds per acre of nitrate and 4.5 fewer pounds per acre of phosphate in the runoff stream. 

Researchers also identified landscape plants and designed sensor systems, rain gardens and artificial wetlands that can be used to filter sediment, chemicals and plant-damaging pathogens out of runoff from nurseries and greenhouses. Filtering runoff protects surface waters and allows reuse of runoff water for irrigation. The project’s findings on using alternative sources like laundry water, pond water and salty water for nursery and greenhouse irrigation could save millions of gallons of freshwater for other uses.