Issues with the quality of your water source can lead to problems down the road. Here’s how you can get ahead of them.

University of Florida Horticulture Professor and Extension Specialist Paul Fisher is focused on grower education across all stages of plant production. In one of his recent “Five Tips for Horticulture” YouTube video series (, Fisher offers advice on how growers can test the chemical quality of their irrigation water.

Step 1: Sampling

At least once a year, send a water sample to a commercial horticulture lab for a complete analysis of pH, EC, alkalinity, and essential nutrients, as well as ions such as sodium chloride and fluoride. You can collect a sample by flushing water through your irrigation lines for five minutes (so you’re not sampling water that’s been sitting in the pipes), then collect around two cups of water using a specialized container or an empty drinking water bottle.

Step 2: Testing Frequency

It’s important to do regular water testing weekly or monthly.

Step 3: Interpretation

You may want to send in both a water sample and a nutrient solution for analysis at a lab. Once your results come back, use an online tool at, which was developed by Fisher, Dr. Rosa Raudales at the University of Connecticut, and Dr. Bruce MacKay from Thomas Baine Ltd. in New Zealand. To use the WaterQual tool, go to the site, select “Tools,” and scroll through the decision support tools related to irrigation and water quality. Choose the WaterQual tool and enter in the results that you get from the laboratory analysis of your irrigation water. Click on “Interpret,” and the tool will provide an analysis of the numbers.

Step 4: Take Action

Solutions will vary depending on what your water analysis tells you. Check out the “Tackling Water Problems” table on this page for the most appropriate advice.

Step 5: Follow up for Advice and Training

Talk with experts, such as university researchers or consultants, to decide on the appropriate long-term remediation. You can also find resources on the website, including information on the University of Florida’s range of greenhouse production.

Tackling Water Problems

The chart below outlines a number of potential issues that could comp up from ions that are dissolved in your irrigation water, and how to manage them.

Reprinted with permission from Greenhouse Grower, April 2021.