Control Mold in Greenhouse

Asked February 10, 2016, 11:06 AM EST

May I ask you, I have a lot of Mold in Greenhouse.I grow organic. I spray M-PEDE 3oz/Galon Water, but not enough. Would you give me any kind of chemical. Please help me. Thank you very much Ken Suzuki

This chemical made by GOWAN company. Active Ingredients( Potassium Salts of fatty acids)

I spray 3 days ago 2oz/ gal. water. But came back 3 day now.
So now I try 3oz/Gal water, but I am not sure ,it will be OK.

Sussex County Delaware greenhouse mold organic greenhouse production organic pest management

1 Response


The control of mold in any situation depends on what type of mold it is. The product that you have used, the potassium or phosphorus acids salts solution, is effective in control of the oomycete fungus-like water molds. If you have a visual colored or dark mold, it may be a true fungus, or may actually be algae. The M-pede is an insecticidal soap with the potassium salts and will not be effective against true fungi and algae.

You should use a more general use disinfectant, according to the directions on the label. The label is the law, and some products are not allowed for use in greenhouse organics.

You could use a 10% bleach solution with a couple drops of dish soap, allow to soak on surfaces for 5-10 minutes and then rinse. Otherwise you could use

quaternary ammonium – sold as Green Shield or Kleen Grow – not for use on porous surfaces like wood, but commonly used in the greenhouse industry for sanitizing. You could also try hydrogen dioxide – sold as Zerotol or Oxidate – also not for use on wood. Mix these products according to their label rates, and always use a fresh solution. Allow contact products to air dry on surfaces for 10 minutes. Then rinse. Be careful not to get these products on the plants as it may cause some damage. Some products such as Zerotol are more corrosive than others, so please wear safety glasses and gloves when applying.
If you use a sanitizing product about once a month, you should not have a problem with mold or algae.

Thank you for contacting Cooperative Extension,