PET Potting Method

[isurus79]

Originally Posted by estación seca

Steve, a U of AZ soil scientist lecturing to our local branch of the rare fruit growers told us no available formulations of time-release fertilizer pellets last more than a couple of weeks in our summer heat outdoors. He told us not to use them on outdoor plants in the summer. I don't know how often you get above 100 F / 38C. He said they're fine for winter annuals and vegetables, and for house plants.

He also told us 100% of ammonium sulfate applied to the soil in summer here is taken up by the plant, or converted to molecular nitrogen by soil microflora, within an hour.

We were above 100 degrees for 51 days this summer and the pellets worked very well. I've still got plenty in my pots right now.