Hey guys, I noticed over the last two days the leaf tips of my main cola and turning yellow/brown and curling upwards a bit, but only on the main cola closest to the light all the other fan leaves seem to be doing well and the plant seems all around happy otherwise. The only changes I have done in the last week to the plant is cranking up the light intensity so that the top canopy reads 720 Par (which is about 150 higher then last week) and started feeding it lightly with potassium, and black strap molasses, and the buds have definitely started swelling up more, but I don’t wanna stress the plant out or be burning it. I’m under a full spectrum LED light board 200watt. Grow conditions are 78.7 on average, 50% humidity, watering everyday with a liter and a half of water fed from top and bottom. Thanks for your guys knowledge and advice in advance!!!
Tip burn isn’t a bad thing and is usually indicative of a little excess nitrogen. Excess nitrogen doesn’t become a real problem until you start seeing dark green, waxy leaves. Keep doing what you are doing.
Thanks brother, I wasn’t to concerned about nitrogen levels at all this grow never once had any curling fan leaf edges or dark waxy leaves, I learned my lesson on my very first grow the hard way about how a little bit of nitrogen goes a long way and when they are in flower it’s bad news 
. You don’t think my light would be causing that or anything ?
I’ve been here in this forum for nearly 5 years and have never seen a real case of actual light burn. I run all of my plants at 1,100 PPFD and have never had a problem. It’s bro science imho. It is most certainly not the cause of tip burning.
Fair enough I have never myself seen it happen from LED either, I have seen it with HPS lights, but that’s more common. Out of curiosity at that PPFD level at you supplementing CO2?
CO2 isn’t effective until 1,200+ PPFD. Managing other environmentals for CO2 is a PITA and I just don’t have the time to deal with dialing everything in so tight. I don’t know any experienced growers who use supplemental CO2.
It is most likely due to the heat put out by MH/HPS rather than light intensity.
Fair enough brother! Id looked into it but I haven’t ever ran my ppfd high enough to even consider needing it and I agree all the shit I have read about it does sound like it would be a pain!
Me either. I drop my lights to 12 inches in flower. No burn. Most damage is from heat at canopy from lights i have noticed myself.
Cannabis Light Burn & Light Bleaching Symptoms & Solutions! hopefully link is ok.
This is a good article. I see light burn as in the tips of the leafs changing color. The difference between the nitrogen tip burn and light burn is the nitro burn is more brownish/orange tips. Light burn is more of a yellowish. Strange how others have not seen this. I start to get burn in the 1050 ppfd range. Consecutively and with different strains. I favor indica dom hybrids tho. Maybe others are running sativa’s that can take a little more. Accurate light readings are critical indoors imo.
One more thing to add. Alot people run insanely high ppfd levels. To each there own. But trust me, try a grow with avg of 800 ppfd in flower, the bud will be alot better. From experience and school of hard knocks.
Lack of K will also cause yellow tips. And you are 100% on the ppfd, I learned quick you can give them too much light without burning them, but growth and yield will suffer!
Worked well.
Thank you.
Another source for reading “homework”.