As the horticulture industry becomes more focused and attuned towards Best Management Practices, it has become all the more important for growers to take a good hard look at irrigation water quality. Water treatment strategies are more frequently involved today than ever before in Best Management Practices. Implementing a strategic water program can assist in growing healthier plants and lowering the overall cost of operation while abiding by Best Management Practices.
Though there are multiple reasons and benefits why irrigation water treatment is important to a successful and responsible growing operation, there are key benefits to justify such a program. Depending on the requirements of a greenhouse/nursery, those reasons can vary in importance.
Here are the top six reasons for implementation of a water treatment program, not in any relevant order.
1. Biofilm In Irrigation Lines Can Cause Nutritional Deficiency
Biofilm is made up of various microbes both pathogenic and benign, and they attach to the inside of irrigation lines. These microbes feed off of nutrients meant for plant material. This leads to an increased use of fertilizer to maintain proper nutrition or the plant will become nutrient deficient.
2. Irrigation Lines With Biofilm Causes “Clean” Water To Turn Dirty
Relatively clean water from cold, deep wells have low bacterial and fungal counts and can constantly be inoculated with harmful pathogens. Essentially taking clean water from the source and running it through the biofilm will spread diseases onto plants through simple irrigation. Water from the irrigation lines can have over 10 times the pathogenic loading when compared to source water.
3. Biofilm Can Cause Irrigation Line Clogging
Biofilm in the irrigation lines can cause water efficiency issues. Biofilm can constrict the surface area of a line causing pressure and flow problems. Also, the algae and microbes that make up the biofilm can break off and clog irrigation heads. These issues can contribute to plant stress and a weakened immune system from inefficient watering.
4. Irrigation Water Can Carry Harmful Plant Pathogens
Well water is typically much cleaner then pond water, but they both can contain harmful bacterial, fungal and algal pathogens. A variety of plant issues can be sourced from the water and not previously thought of as factors. There are many plant symptoms that go misdiagnosed. Proper testing and treatment of the water can lessen the guesswork of a grower.
5. Pythium And Phytophthora In Irrigation Water
Many research studies link Pythium and Phytophthora to irrigation water. Dr. Paul Fisher discusses these issues and studies in his “Water Treatment Guidelines” article, which can be found on University of Florida’s Water Education Alliance website.
6. Increased Cost Associated With Bad Water Quality
This last reason to treat irrigation water can function more as a summary than as a standalone, because when you take all the above outcomes of mismanagement of irrigation water you increase overall production cost. Biofilm and other pathogens found in irrigation waters causes stress, nutrient deficiency, stunted growth and devastating plant diseases. To compensate, more costly chemical sprays are put in rotation, nutrient feed is increased and there is a surge in labor. All this amounts to more time and money spent.
There are many economical and effective solutions to water quality issues. Previously thought as an added expense, proper water management can actually lead to a decrease in overall production cost. Different approaches can be made — shocking irrigation lines periodically, constant treatment of irrigation water, periodic treatment or even treating the source. Activated Peroxygen Chemistries (APC) has been researched extensively and deemed a very effective and sustainable solution for treating water. Some other options include copper ionization, chlorine and ozone. There are companies that specialize in implementing such programs and can offer water testing and associated services to help implement proper strategies and solutions. University Extension is also a reliable source for irrigation needs.