Lighting Expert question about LEDs and optimal temperature

[Death The Cultivator]

That is good to know. What are your leaf temps usually compared to room temp? Does it change with how close/far the light is from the canopy?

If everything is consistent leaf temps are between 76-81f usually. Ambient temperature sits around 78-84f. I've ran my lights 4 inches away and 36 inches away, it tends on depend on airflow and the temperature in the room in intaking from. The temperature can change based on light distance but it depends on the lights. I've been almost exclusively growing Ace Seeds landrace sativas for two years with these same lights.

I'm running 500 watts on these you check my current journal below

F | T |F Growery: Ace Seeds Limited Editions+Optic Foliar Testing

Now technically Zamaldelica x Kali China isn't a limited edition anymore but it was lol. Welcome to the Grow My cloning efforts have been less than satisfactory and I was behind due to life issues so this grow is late. Going to be running Zamaldelica x Kali China again with 12 clones...

• Death The Cultivator
• May 20, 2020
• Comments: 65
• Category: Cultivators Club
• Blog: F | T |F Growery

 

[benawhil]

Nice set up! You got some really nice medicine going!

 

[PlatinumGrows]

I'm running a DIY Bridgelux EB2 build between 76-84f depending on the time of year for flower. I've noticed no significant difference with a full spectrum at different temperatures. I try to keep the temperature down as it improves the efficiency and life span of the LED diodes and drivers. What is more important is maintaining the proper VPD because it regulates the stomata

Excessive heat with low humidity causes transpiration to happen too quickly and cause nutrient lockouts like CaMg when humidity is below 40%

Excessive humidity can prevent the stomata from not being able to transpire as well.

Vapor Pressure Deficit VPD Calculator - Dimlux Lighting - The Best Grow Lights

Vapor Pressure DeficitCalculator Calculate both Room VPD and Leaf VPD automatically Just enter the value below to generate the VPD values for your room and your plants. You’ll need to know the room’s temperature, relative humidity, and the plant’s temperature. We recommend calibrating your...

www.dimluxlighting.com

Buuuuuuut first off c02 exhale bags are a waste of money. You have to run a sealed environment with no air exchange to reap the benefits plus there is no method to control the amount of c02 released. Unless he's running a mini split with a humidifier and dehumidifier he's wasting his money. 800-1200ppm is the acceptable range for c02 injection and if used too late in flower will cause airy buds.

lll say it was complete bull. I use a $40 IR gun from Home Depot that I have not had trouble with for measuring leaf temperature. Also CLW and Blackdog both produce biased articles for their marketing.

Not to hijack this thread but I just plugged my numbers in this calculator and I can see that I’m not within my optimal ranges I’m not terribly far off either but maybe this impacts my light distance from my plants ? If my KPA is too high maybe I need my light even further away ?

 

[Death The Cultivator]

Not to hijack this thread but I just plugged my numbers in this calculator and I can see that I’m not within my optimal ranges I’m not terribly far off either but maybe this impacts my light distance from my plants ? If my KPA is too high maybe I need my light even further away ?

Do you have an infrared thermometer? Has to be used to take surface temps. So it's ambient/leaf surface temperature in a sliding relationship with each other.

If your kpa is too high then it's dry and you might have transport issues with Ca below 40% humidity. More so that the environment needs to be regulated within VPD ranges so that your plants and optimally photosynthesize the light you are providing them.

 

[WildBill]

Update...I found his probable source for the 85 degree optimal temp for his specific lights: https://www.blackdogled.com/lst#Cannabis

Big buck light!!!!!!!!!

 

[Kyote]

I go by VPD and check canopy leaf temperature (infrared) and the leaves at canopy level are usually 2 to 3 degrees lower than temperature in the tent. imo, temps mean very little if RH isn't added to the equation. See VPD calculator - I am new to indoor, only 2 runs. The first one, I did most everything wrong. On the 2nd grow, I went by VPD numbers and had a decent grow. I'll stick with the VPD numbers this fall and winter when i grow inside again, as I do think that provides optimal RH/temp environment.