When to switch up light intensity with LEDs

[Keeno]

Tom I'm sorry, I misread, my advice doesn't work if there are 25% increments. Do you have any room above the light? You could whack it up to 100% and raisie it a bit. You would be shocked the drop off in intensity a few inches can make, this would allow you to turn it up, and lower the light daily.

[Tom1974]

Tom I'm sorry, I misread, my advice doesn't work if there are 25% increments. Do you have any room above the light? You could whack it up to 100% and raisie it a bit. You would be shocked the drop off in intensity a few inches can make, this would allow you to turn it up, and lower the light daily.

No worries man, I turned it up to 100% this morning and raised it to its max

The highest reading on the tallest canopy was 65,000

Surely they won’t bleach at that reading even if the lux meter isn’t 100% accurate it can’t be far off can it?

What’s surprising though is one’s directly next to the highest reading or in front/behind are way off that reading and they don’t look like they are in the shade or anything

[Tom1974]

Lower the light daily, please could you explain buddy?

[Keeno]

Lower the light daily, please could you explain buddy?

As in hanging height.

[Tom1974]

Lower the light daily, please could you explain buddy?

As in hanging height.

Right, I’ve just whacked it up to it’s max height now and got a reading of 65,000 but the aim is to then start loading the unit bit by bit again?
How close to the tips of the flowers buddy?
Sorry for my ignorance/stupidity

[seymore_budz]

You could guess this but it would be extremely hard without measuring a few parameters of your room. You would need to measure the CO2, Temprature, Humidity & PPFD. Then you could calculate the optimal PPFD with a few calculations. This can be expensive as the equipment to monitor the co2 levels and light output in real-time costs a pretty penny. Also, I'm not sure if that's the full picture.

Stepping into the realm of theory, cannabis thrives all over the world and grows in many climates. Like most plants, different genotypes might like a different climate for example, a plant that has been bred for a European climate may prefer less DLI and a cooler climate yet other cultivars may prefer a Mediterranean climate and enjoy warmer conditions and a higher DLI. As far as I'm aware, not much research has been done within that area?

Considering this, my rule of thumb pre quantum and co2 sensor was try to keep the LED around 40-50cm from the canopy. 25% when they're 10" tall. Increase to 50% for the rest of the duration of growth. Then 75-100% throughout the flowering cycle. Of course this all depends on the output of the LED. My largest LED running my flowering op as an efficency of 2.7mmol/J.

I've light bleached some baby seedlings previously with T5s believe it ir not but never burnt my plants with LED even when tops have been less than 30cm from the LED and its been whacked up. More than often, its not the light that burns things and its the unfavorable environmental conditions like extreme heat, low humidity and crazy amounts of PPFD.

[Tom1974]

You could guess this but it would be extremely hard without measuring a few parameters of your room. You would need to measure the CO2, Temprature, Humidity & PPFD. Then you could calculate the optimal PPFD with a few calculations. This can be expensive as the equipment to monitor the co2 levels and light output in real-time costs a pretty penny. Also, I'm not sure if that's the full picture.

Stepping into the realm of theory, cannabis thrives all over the world and grows in many climates. Like most plants, different genotypes might like a different climate for example, a plant that has been bred for a European climate may prefer less DLI and a cooler climate yet other cultivars may prefer a Mediterranean climate and enjoy warmer conditions and a higher DLI. As far as I'm aware, not much research has been done within that area?

Considering this, my rule of thumb pre quantum and co2 sensor was try to keep the LED around 40-50cm from the canopy. 25% when they're 10" tall. Increase to 50% for the rest of the duration of growth. Then 75-100% throughout the flowering cycle. Of course this all depends on the output of the LED. My largest LED running my flowering op as an efficency of 2.7mmol/J.

Awesome information mate, I’m learning so much on here cheers

[seymore_budz]

You could guess this but it would be extremely hard without measuring a few parameters of your room. You would need to measure the CO2, Temprature, Humidity & PPFD. Then you could calculate the optimal PPFD with a few calculations. This can be expensive as the equipment to monitor the co2 levels and light output in real-time costs a pretty penny. Also, I'm not sure if that's the full picture.

Stepping into the realm of theory, cannabis thrives all over the world and grows in many climates. Like most plants, different genotypes might like a different climate for example, a plant that has been bred for a European climate may prefer less DLI and a cooler climate yet other cultivars may prefer a Mediterranean climate and enjoy warmer conditions and a higher DLI. As far as I'm aware, not much research has been done within that area?

Considering this, my rule of thumb pre quantum and co2 sensor was try to keep the LED around 40-50cm from the canopy. 25% when they're 10" tall. Increase to 50% for the rest of the duration of growth. Then 75-100% throughout the flowering cycle. Of course this all depends on the output of the LED. My largest LED running my flowering op as an efficency of 2.7mmol/J.

Awesome information mate, I’m learning so much on here cheers

No problem. Also remember that this is all based on the plants health. If you're pushing the lights but your PH is out or they're suffering from nutrient deficiencies etc then they might not like all that light. The same way we can turn the pumps up by providing more light, if your plants are not 100% its best to turn those pumps down too. This will slow growth but at the same time give the plants time to focus on recovery. These skills cannot be taught within a few paragraphs here and come with experience.