Light Intensity Through Plant's Cycle

[leo1991]

Hello all. From what I've read I have finally understand about light intensity and lux levels. So my research is;

1)seedling stage 5000-7000 lux
2)veg phase minimum 15000-20000 lux ,optimum 40000
3)flower phase minimum 40000
Optimum 65000

So the questions are
1)are my calculations right? All cannabis plants react the same on the intensities?
2)when do we enter veg phase and when seedling phase ends?

That's all folks thanks for your time!

 

[FarmerDaniel]

Lux is designed for measuring light for human use. Commercial buildings and such. Here's a crash course for your googling adventures.

You want to measure and talk in terms of PAR not lux. Photons are measured in moles per day and micromoles per second. The DLI is daily light integral. Cannabis wants a DLI between 22 and 65 moles. That's 22 million micromoles. PAR meters measure micromoles. Some general guidelines are usually said like this:

200 PAR for clones and seedlings
400 PAR for veg
800-1500 PAR for flower

Understand that the DLI is for a 24 hour period so if you're running 24 hours at 400 vs 12 hours at 800 your ate delivering the exact same daily light integral.

Lux meters will not get you the information you want. It will weight greens and yellows more heavily than blues and reds so it will not show you accurate growing power

 

[leo1991]

Lux is designed for measuring light for human use. Commercial buildings and such. Here's a crash course for your googling adventures.

You want to measure and talk in terms of PAR not lux. Photons are measured in moles per day and micromoles per second. The DLI is daily light integral. Cannabis wants a DLI between 22 and 65 moles. That's 22 million micromoles. PAR meters measure micromoles. Some general guidelines are usually said like this:

200 PAR for clones and seedlings
400 PAR for veg
800-1500 PAR for flower

Understand that the DLI is for a 24 hour period so if you're running 24 hours at 400 vs 12 hours at 800 your ate delivering the exact same daily light integral.

Lux meters will not get you the information you want. It will weight greens and yellows more heavily than blues and reds so it will not show you accurate growing power

well that's a really solid answer dude. Thanks a lot. Well until I buy a par meter should I stick with this measurements? I recently bought a lux /foot candle meter.

 

[FarmerDaniel]

Well two different lights could each show 50,000 but read completely different PAR ratings so it's hard to say.

At least you can know what you're reading when your lights are at a certain height. Then you can use that for future reference just to know how current intensity compares to yesterday's and the day before. So it's better than nothing to have a lux meter but leaves a lot to be desired in terms of actually telling you what you're giving your plants. I know I'm pretty close to 30 moles at canopy right now because I'm running 460 par for 18 hours. 460*60*60*18=29,808,000 moles. Before I had the meter i had no idea how much par changes from just a half inch. I was always guessing. Sometimes running my plants too hard and sometimes not nearly as hard as I could. If you want to maximize get a par meter.

I use the Apogee mq500. It's sensor is calibrated for reading leds better.

 

[leo1991]

Well two different lights could each show 50,000 but read completely different PAR ratings so it's hard to say.

At least you can know what you're reading when your lights are at a certain height. Then you can use that for future reference just to know how current intensity compares to yesterday's and the day before. So it's better than nothing to have a lux meter but leaves a lot to be desired in terms of actually telling you what you're giving your plants. I know I'm pretty close to 30 moles at canopy right now because I'm running 460 par for 18 hours. 460*60*60*18=29,808,000 moles. Before I had the meter i had no idea how much par changes from just a half inch. I was always guessing. Sometimes running my plants too hard and sometimes not nearly as hard as I could. If you want to maximize get a par meter.

I use the Apogee mq500. It's sensor is calibrated for reading leds better.

thanks for your time! I fully understood after I googled some more information!

 

[Cannabisvalleyfarms]

Hey guys. So at 20% im getting 1800 lux. Is that bad or good?

 

[freezeland2]

Hey guys. So at 20% im getting 1800 lux. Is that bad or good?

What kind of light are you running? be sure you have the right light source selected in the app so you get accurate readings. 1800 Lux isn’t enough for anything IMO.

 

[Cannabisvalleyfarms]

Hey freezeland2. Im running California lightworks 800w. Ya i choose led in the options

 

[Cannabisvalleyfarms]

This is on max right under the light

 

[Cannabisvalleyfarms]

This is on max