I’ve finally got it perfect running at 81-83 degrees f and 56-60% humidity. It made a world of difference
LED and Calmag issues.
- Thread starter 3rd Monkey
- Start date
I was a disbeliever when it came to how different HPS and LED make the plants react. VPD is way more important with LED lighting because of the infrared factor and heat on the plant leaf. People would just tell me run your led room a litter warmer but never explained why. The temp you run at isn’t as important as the humidity. The vpd is much more critical with LED lighting in my experience. Early flower keep your vpd low , around 1.2 if possible. I can’t get mine that low but I did get it to 1.5 and those bitches took off in 24 hours. When my humidity was to low and the vpd was around 1.9 they wouldn’t eat, they wouldn’t grow and they are were deficient and suffering. Just from adding the humidity from 48% to 56-60% they took off. Trust me on this, I found out the hard way. Get some push sensors , put them even with your canopy…. With LED don’t use a leaf adjustment temp just leave it at zero. HPS use a 3 degree adjustment temp. Keep your vpd early flower 1.1-1.5 and late flower 1.2-1.6 and your plants will love you.
My problem is I have my chiller in my flower room which is sucking the humidity out. I have the chiller exhausting out for heat purposes. Once I move the chiller to another location the room will be completely sealed. I’m also wasting co2 so it’s imperative I relocate my chiller ASAP
Nutty sKunK
Well-Known Member
Theres the problem for me. I extract out the room so it’s gonna cost me 4-5x more to heat the damn things than to use the light.
Moving ‘back’ to CMH for the infrared
You can always slow down your extraction or use a timer so it maintains a certain temp and humidity
sweettooth
Active Member
Nice looking strain there. Is it Jelly Breath?
sweettooth
Active Member
I may throw in a couple of hps bulbs over winter as it's cheaper than using heaters, the last combined hps and led grow I did was great, not enough cash in the kitty to upgrade to cmh yet. humidity is the key here, I follow a lot of growers who grow fantastic looking plants at 25 degrees which goes against all the recommendations I hear of upping the temps. I haven't yet tried as currently using a metal halide light over some cuts to perk them up, they got quite cold and stunted under led but running RH at about 70 with 26 degree temps and they're perking up
Flatrate
Well-Known Member
It is Banana Punch x Tropical Zkittlez by Tiki Madman.
jarvild
Well-Known Member
I never pay attention to VDP and my plants grow fine no matter what type of lighting I'm running, when you realize that the best HPS might get you 1.7 umols and compare it to most modern LED's at 2.4+ umols and you realize that every 1 umol is to the 10th power you understand that LED's are 1/3 more powerful than an HPS
twentyeight.threefive
Well-Known Member
Lul wut?
budman111
Well-Known Member
bk78
Well-Known Member
Jimmy Slade
Well-Known Member
I think we're clear for take off.
Take VPD serious one grow and actually keep it perfect. Then come back here and say VPD doesn’t matter. And yes the extra power coming from the LEDs minus the IR with a high VPD will not open the stigmata of the leaf and your plants will go bye bye. Keep the VPD at proper levels and you will enjoy a rewarding harvest. Facts
jarvild
Well-Known Member
Do you have side by side comparisons of plants grown under prefect VPD vs non VDP plants ?
Actually I do literally side by side. A perfect healthy canopy and a half ass canopy but I can’t take pics until tomorrow when the lights come on. I’ll post them for you guys to show how much of a difference it makes
The main thing a high vpd will effect is the uptake of calcium and magnesium. People think they have a calcium deficiency add more calcium. Don’t do this, it makes it worse. If you have problems with a high vpd or if you don’t know what that is. If you have for example 80 degrees temp and 45% humidity your vpd is to high meaning your plants will not intake nutrients and water the proper way. If you want a quick fix with a high vpd lower your nutrients drastically so they uptake more water than nutes. Lower your calmag and the ppm of your nutes and this will help the plant survive. Im
Not the best at explain these things but I hope you understand what I’m getting at. You can also lower the output or dim your lights, that will also help with a high vpd. High powered LED lights with a high vpd is a recipe for death. Same goes for HPS but the infrared will help open the stomata of the plant leaf. I hope this helps and I hope I explained it right. I know how some of you feel when a grow isn’t going right.
Not the best at explain these things but I hope you understand what I’m getting at. You can also lower the output or dim your lights, that will also help with a high vpd. High powered LED lights with a high vpd is a recipe for death. Same goes for HPS but the infrared will help open the stomata of the plant leaf. I hope this helps and I hope I explained it right. I know how some of you feel when a grow isn’t going right.
drsaltzman
Well-Known Member
I dunno man.
I’m no master grower but these plants have been chugging along under COB LEDs in 78-80° and humidity never lower than 45%. They are nowhere near certain death. Well let me rephrase that. There’s certain death in their future but I control that. Flipped the lights Sep 10. Stopped stretching around Oct 1. So they’re 4 weeks into flower if you count those things.
I’m no master grower but these plants have been chugging along under COB LEDs in 78-80° and humidity never lower than 45%. They are nowhere near certain death. Well let me rephrase that. There’s certain death in their future but I control that. Flipped the lights Sep 10. Stopped stretching around Oct 1. So they’re 4 weeks into flower if you count those things.
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Locktopus
Member
I use COB LEDs... Gen 7 now... I have ran into calmag issues in the past with shittier LED lights especially using jacks (don't know why, you;d think it would be great but in all honesty, it was probably the old LED technology) and AN trash as an experiment around 4 - 5 years ago when COB first came out to market.. I just use dynagrow now with 4 - 10ppm RO water and have zero calmag issues with modern LEDs and I never run "calmag" itself at all throughout the entire grow even with RO, just dynagrow regimen cut by 50% in hempy buckets... week 7, switch to nothing but freeze dried organic horticultural coconut water from buildasoil and week 8, flush and my hydro shit comes out like butter and sugar made love together.
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drsaltzman
Well-Known Member
I’m a minimalist.
3 gallon felt pots.
Roots 707.
300w COB in a 2x4 tent.
GH Floranova Bloom all the way through.
Tap water.
I use Recharge every other feed.
And a little Mykos in the transplant hole.
Very rarely run into trouble.
Haven’t used Calmag in years.
If you can grow, you can grow.
Your plants aren’t gonna die under LEDs because your humidity is 40% and your temp is 80°F.
3 gallon felt pots.
Roots 707.
300w COB in a 2x4 tent.
GH Floranova Bloom all the way through.
Tap water.
I use Recharge every other feed.
And a little Mykos in the transplant hole.
Very rarely run into trouble.
Haven’t used Calmag in years.
If you can grow, you can grow.
Your plants aren’t gonna die under LEDs because your humidity is 40% and your temp is 80°F.