Should I add hypochlorous acid to my soil-based crops?

We don’t recommend using hypochlorous to disinfect soil because it is an oxidizing solution, which means it will focus on breaking down the nearest organic compounds first. Soil is full of organic material, so the disinfecting potential of hypochlorous will be greatly reduced as soon as you add it to the soil. However, it can be effectively used to sanitize growing media such as clay pebbles or perlite, and can still be added to water lines in soil-based systems to prevent algae or biofilm blockages in the line. It is also great for foliar applications to keep powdery mildew away!

Can hypochlorous acid be added at the same time as liquid nutrients?

The short answer is no. When hypochlorous comes in contact with nitrogen, it is rapidly converted to chloramine, which is much less effective as a sanitizer. Therefore, it's best to add HOCl separately from nutrients, either on different days (if possible) or at different times of the day. Always test your pH and ORP after adding anything to the water to make sure you're still getting the maximum benefits from free available chlorine. If needed, you can always top up the system with more HOCl.

Can I use hypochlorous acid in a hydroponic system with beneficial bacteria?

Hypochlorous acid is an oxidizer, which means it targets bacteria and inactivates them. In most cases, this is good! However, if you're adding in beneficial bacteria to your system, then running a constant dose of hypochlorous acid at the same time won't do you much good. The hypochlorous will be used up trying to inactivate the bacteria, leaving your system defenseless from the harmful pathogens those good bacteria were intended to prevent. That being said, you can still use hypochlorous for other greenhouse functions, such as sanitizing tools, foliar applications, post-harvest sanitation, and flush-to-waste system cleaning. 

Will hypochlorous eliminate fungal gnats, aphids, and other pests?

There is not currently any peer-reviewed research about the efficacy of HOCl against insects and pests. However, pests are often drawn to systems where there is bacteria available for them to feed on (ie; fungal gnats feed on algae and fungi). Keeping your growing system clean with HOCl can put you at less risk of a pest infestation, but we can't guarantee it will be effective against any ongoing infestations. An ounce of prevention is worth a pound of cure!

Photo by Matt Hanns Schroeter on Unsplash

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