I'm involved in a similar thread on another site which is why I posted info re. photos even though I've grown autos. Per my previous post, I get my seedlings to a DLI of 25 and, once they hit veg, 45 - 50 mols. I'd love to have a grow where I can get 45 mols to the entire canopy. Maybe I'll get there one day!
The reason I went with 45 mols is that it fits in the generally published values where cannabis can grow, it's the value that the programmer at Photone recommended when I asked him about DLI for autos, and it's well within the DLI if you use a PPFD of 780 for 18/6.
My current grow is 2 Gorilla Glue autos that are in late flower. I've got about 20 colas that stand above the canopy, some are close to canopy height, about a half dozen are up to 1' above the canopy so it's not easy to get "the canopy" 45 - 50 mols. Over the last few weeks, I've sort of tossed in the towel on getting an evenly lighted canopy. I don't like that particularly (as a programmer, I've been telling computers what to do for 30 + years and now I have a plant that won't behave?) but I'm resolved to try and get good light where I can, console myself that the little guys in the corners aren't doing it on purpose, and am watching out that the big guys in the front don't get so much light that they start to fox tail on me.
Below is the light into entry in my daily journal, which I keep in Excel. I sample most of the colas in the canopy using an Apogee.
256 - the wattage of my light (a Growcraft X3 "full cycle" light)
18 - lights on hours
# - the sequence number
PPFD - µmols
DLI - the PPFD * lights on hours
Values in blue are < 35 mols
Values in black are >=35 to 45 mols
Values in red are > 45 mols
The values at the bottom include only values that are >= 35 mols
Lower left in bold is the standard deviation of the PPFD value
PPFD and DLI columns are the average values
Lower right in bold is the STDEV of the DLI values.
The %'s indicate the number of colas in a given DLI//PPFD band. The goal would be to have 0% in blue but won't be happening with this grow. OTOH, I put values in red to prompt me to make sure that those plants aren't showing any signs of light avoidance//light damage. I'm being cautious because I believe that damaging plants and then turning down the lights or reducing nute strength is more detrimental to a harvest than it is to slightly under feed or "under light" a grow.
This is my third grow so my focus is to "get to done" with a good crop rather than trying to push things hard and ending up with leaf damage or foxtails.
The reason I went with 45 mols is that it fits in the generally published values where cannabis can grow, it's the value that the programmer at Photone recommended when I asked him about DLI for autos, and it's well within the DLI if you use a PPFD of 780 for 18/6.
My current grow is 2 Gorilla Glue autos that are in late flower. I've got about 20 colas that stand above the canopy, some are close to canopy height, about a half dozen are up to 1' above the canopy so it's not easy to get "the canopy" 45 - 50 mols. Over the last few weeks, I've sort of tossed in the towel on getting an evenly lighted canopy. I don't like that particularly (as a programmer, I've been telling computers what to do for 30 + years and now I have a plant that won't behave?) but I'm resolved to try and get good light where I can, console myself that the little guys in the corners aren't doing it on purpose, and am watching out that the big guys in the front don't get so much light that they start to fox tail on me.
Below is the light into entry in my daily journal, which I keep in Excel. I sample most of the colas in the canopy using an Apogee.
256 - the wattage of my light (a Growcraft X3 "full cycle" light)
18 - lights on hours
# - the sequence number
PPFD - µmols
DLI - the PPFD * lights on hours
Values in blue are < 35 mols
Values in black are >=35 to 45 mols
Values in red are > 45 mols
The values at the bottom include only values that are >= 35 mols
Lower left in bold is the standard deviation of the PPFD value
PPFD and DLI columns are the average values
Lower right in bold is the STDEV of the DLI values.
The %'s indicate the number of colas in a given DLI//PPFD band. The goal would be to have 0% in blue but won't be happening with this grow. OTOH, I put values in red to prompt me to make sure that those plants aren't showing any signs of light avoidance//light damage. I'm being cautious because I believe that damaging plants and then turning down the lights or reducing nute strength is more detrimental to a harvest than it is to slightly under feed or "under light" a grow.
This is my third grow so my focus is to "get to done" with a good crop rather than trying to push things hard and ending up with leaf damage or foxtails.
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