Just bumping before 2022 is over. If you’ve followed along, just know that USU has updated a few things since that “maximizing cannabis yields” video was posted.
PLS is Peter’s most common fert for peat-based (promix) DTW greenhouse growers. It’s 40% ammoniacal, which is done to combat the rise in peat media pH over 100+ days of use in annual season settings. It’s a system that greenhouses everywhere use, including the ones I work in. USU uses it because it’s ubiquitous, simple to use, can almost be mixed by eye, and more specifically USU needs a datum plane, a standard feed, to study OTHER things like spectral effects of different LEDs. Notice they aren’t studying THC/terpene/secondary metabolite production as a function of nutrition, and never will without Fed licensing.
People find his Maximizing video and may assume these methods were the result of years of research into best methods for cannabis production, or at least “what works in a research setting”. Well… All we know is that these methods are what the USU program uses to standardize X, so that they can go study Y. The feed and mix is the same stuff we use for leafy veggies, but not for tomatoes, strawberries, or other fruiting crops… we have specific feeds for those and indeed might phase in things at different stages of life.
Lastly, Dr. Bruce offers a TON of between-the-lines info in his recent youtube offering on Phosphorus for example where he shares that some cultivars need way more than PLS. Which ones?!
Happy 2023 all! PM me if you want to chat on the topics more. I know I sucked up all the air from this thread.