I don’t believe there is from my limited research, but I believe in general some people try to run autos harder, nutrient wise atleast. I don’t really know anything about autos I’m sorry. If your having ph issues though, you should definetly post on plant problems and people more experienced than me can help
Now that’s an interesting statement = " I believe in general some people try to run autos harder, nutrient wise atleast”.
I know that I have, though I’ve only done 1 auto grow and 1 photo grow. My current grow is Gelato autos and I just now finished swapping in a res at…145/500 PPM. Yeh, totally weird but I won’t clutter up this thread with my meshugas.
) I don’t think that using the average is a good approach.
Let me help you out with some quick DLI math while I answer the rest of your question.Now that’s an interesting statement = " I believe in general some people try to run autos harder, nutrient wise atleast”.
My impression is that auto growers use lower levels of nutes than people doing photos.
Back to your question about DLI in late flower. I’ve got to read the Chandra paper again. Going back to your question, one thing that I’ve found after using an Apogee for a few months is that I can tell you how much PPFD is falling in a lot of places on my plants but I can’t tell you what my DLI is.
I just took these readings on the plants. There are four plants but the canopy on one (“Jeff") is so much lower I don’t take readings on it.
Looking at the values below, what’s the DLI? The average PPD is 574 and that value is used in the DLI column but, the PPFD down the center averages 631 while the average along the front row is only 527. That’s a range of 100± µmols ≈ a difference of 6 moles for DLI. That’s a lot.
My thinking? Even without CO2 (and we’re at 415 on Manual Loa and much higher in metro areas but I’m not willing to pony up $60 for a C)2 meter
One of the drivers for the idea that there’s little value in going over a DLI of 40 is diminishing returns in yield and one of the factors used to arrive at that is electricity cost. I found a site that ran calculations and the cost increase was slight - I should have bookmarked it - vs the increased yield of even a few percent. That’s for a commercial grower. For a personal grower, I’d prioritize the cost difference pretty low because, overall, the cost to run an LED is pretty low.
Right now my light is running 154 watts. If I drop 100 PPFD, my wattage will drop to about 130. Call it a 30 watt drop. Even here in the People’s Republic of California, over the course of a month, the 30 watt delta is just under $5 ( ((30 * 24 * 30)/1000)*0.23) that’s 21.6 kWH at 23¢. I can deal with that. I’m quite happy to I get 5% more weed for $5.
With that in mind, my thinking is to push the DLI higher because LED’s can’t cause direct harm to plants and an increase of N% in light will yield an > N% increase in yield. Eventually, you’ll hit the limits that are discussed in Chandra et al but, as Bugbee says, the biggest issue he sees when called in to look at a grow is that growers are leaving money on the table by not using enough light.
View attachment 5019694
I just wanted to add to the last part of your post, I made this whole thread because I don’t want to light bleach and kill my plants. LED’s are strong enough to harm plantsNow that’s an interesting statement = " I believe in general some people try to run autos harder, nutrient wise atleast”.
My impression is that auto growers use lower levels of nutes than people doing photos.
Back to your question about DLI in late flower. I’ve got to read the Chandra paper again. Going back to your question, one thing that I’ve found after using an Apogee for a few months is that I can tell you how much PPFD is falling in a lot of places on my plants but I can’t tell you what my DLI is.
I just took these readings on the plants. There are four plants but the canopy on one (“Jeff") is so much lower I don’t take readings on it.
Looking at the values below, what’s the DLI? The average PPD is 574 and that value is used in the DLI column but, the PPFD down the center averages 631 while the average along the front row is only 527. That’s a range of 100± µmols ≈ a difference of 6 moles for DLI. That’s a lot.
My thinking? Even without CO2 (and we’re at 415 on Manual Loa and much higher in metro areas but I’m not willing to pony up $60 for a C)2 meter
One of the drivers for the idea that there’s little value in going over a DLI of 40 is diminishing returns in yield and one of the factors used to arrive at that is electricity cost. I found a site that ran calculations and the cost increase was slight - I should have bookmarked it - vs the increased yield of even a few percent. That’s for a commercial grower. For a personal grower, I’d prioritize the cost difference pretty low because, overall, the cost to run an LED is pretty low.
Right now my light is running 154 watts. If I drop 100 PPFD, my wattage will drop to about 130. Call it a 30 watt drop. Even here in the People’s Republic of California, over the course of a month, the 30 watt delta is just under $5 ( ((30 * 24 * 30)/1000)*0.23) that’s 21.6 kWH at 23¢. I can deal with that. I’m quite happy to I get 5% more weed for $5.
With that in mind, my thinking is to push the DLI higher because LED’s can’t cause direct harm to plants and an increase of N% in light will yield an > N% increase in yield. Eventually, you’ll hit the limits that are discussed in Chandra et al but, as Bugbee says, the biggest issue he sees when called in to look at a grow is that growers are leaving money on the table by not using enough light.
View attachment 5019694
Yup, that works for me.
Oh, I realize that - it's particles impacting plant matter.I just wanted to add to the last part of your post, I made this whole thread because I don’t want to light bleach and kill my plants. LED’s are strong enough to harm plants
Could this be heat stress? I just moved my driver outside my tent.
My experience has been that excess light causes fox tailing. I ran into it in 2022 at 1250±µmol and once again in my current grow when the dimmer on my grow light failed, setting the light to 100%. One bud was getting > 1300µmol and it ended up fox tailing.
I know this is an old thread, but I recently ran 1100-1300 PPFD and pushed to 1400 PPFD.