Product Q&A

« See More Q&A's

Jim from Homer, Ny writes

What is the mix rate for Monterey Garden Phos Systemic Fungicide to treat root rot of indoor plants (Pelargoniums)

I bought this product from you to cure or control root rot in my Pelargoniums. There is no specific dosage listed for Pelargoniums, which are not real Geraniums. There IS a listing for REAL Geraniums under "bedding plants", but Monterey support told me to use the dosage found under "ornamentals". The dosage (for soil drench) is flaky. It says, 1/2 - 6 FLUID OUNCES per 1 - 5 GALLONS. in other words, I could use as much as 6 ounces per gallon or as little as 1/2 ounce per 5 gallons. At the high end, that's equivalent to 12 TABLESPOONS (36 TSP) per gallon. Whereas the soil drench for bedding plants is 1/8 tsp. I asked Monterey to clarify this, but they got upset at me! All I want to know is what is a SAFE and effective dosage for a soil drench for my indoor pelargoniums.


Unfortunately, typically once the plant is impacted or showing signs of root rot disease, there is no cure or remediation to save the plant. It is recommended to immediately discard infected plants after a positive diagnosis is made and then discard unwanted plants at the end of the season. Disinfect all gardening tools, prep surfaces, as well as gloves and washing your hands when handling soil, clippings or matter from the infested plant to prevent spreading.  Regarding the use of Monterey Garden Phos Systemic Fungicide and since it is not labeled for this application treatment, the advised ornamental rate they provided would be the only thing to go by even though it is a broad range of 0.5 fl to 6 fl oz per 1 to 5 gallons. The low rate is most of the time for preventative applications and the higher rate is for high pest pressure. 

Answer last updated on: 10/03/2022

Was this answer helpful to you? Yes No