Hello All, been creepin around THCFarmer for a few weeks now (home on leave/ work injury-smoking and tending my gardens), a lotta good folks on this site, everyone is cool and respectful(sometimes rare on-line) and "the Dude will Abide"(lol), Im an old Hippie (with no hair anymore) Planted my 1st seeds back in 1979 at 15 yrs old, (i said "old hippie") since then I (we) did many guerilla grows, field scale, grow houses, etc., during Prohibition. Thanks to decriminalization and Legalization, we are relieved of Our Criminal Status(s) ("Praise Jah"). The World would be a much different Place had Cannabis never been Placed on Scedule 1, the World can thank R.M.Nixon for that.(not). All You Farmers have inspired me to come out and Join. My 1st Post is mostly for the Lads who Spend way too much on Lighting(me), and the Geeks(me too) who pour over Clinical Research Papers honing their Craft...(credit to University of Mississippi, lcp growers,funded by Natural Sciences and Engineering Research Council of Canada (Grant# CRDPJ533527-18). Green Relief provided the research facility, cannabis plants, experimental materials, and logistical support.) I found this interesting,
Its been tribal knowkedge that was based on many studies that 1,000 PPFD is the safe upper range of light that Cannabis can handle The research actually shows that Cannabis has no light saturation point (at least up to 2,000 PPFD which is the most that researchers in clinical trials have subjected it to. This recent paper published by the University of Mississippi showed that the Peak Photosynthesis rate in the leaves was reached at 1500 PPFD and 30C/86F at ambient CO2 levels, but the researchers actually found that the rate of transpiration continued to increase up to 2,000 PPFD. What the study actually showed was not that Cannabis requires supplemental CO2 beyond 1500 PPFD (let alone 1,000 PPFD, which is kind of an absurd limit when you consider that sunlight regularly reaches 2,000 PPFD and Cannabis evolved as a Full Sun plant), but instead that CO2 is required when leaf surface temps exceed 30C/86F; which is likely why indoor growers mostly growing under HPS light which emit considerable radiant heat downwards into the plant canopy came to believe that 1,000 PPFD was the safe limit to use without the need for supplemental CO2. This study on the other hand actually tested dry inflorescence yield and found that, while leaf Peak Photosynthesis did seem to top out at 1500 PPFD, actual inflorescence/flower weight yield continue to increase linearly all the way up to 1,800 PPFD and even up to 2,000 PPFD. ""And this was done at atmospheric/ambient CO2 levels"". (of course sealed rooms can disregard this) Heres the link to the Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8144505/
come on darlin, $1700.00 dollars is NOT a lot of money to spend on lights, just think of the weed were gonna grow now !! , thx gromies for a cool place to hang out - enjoy, Chopp
Help! Is my plant dying?
Do it yourself (DIY) lentil root booster