Can anyone help me! Major leaf curl!

Can anyone help me determine the cause of this leaf curl? i did my own research and thought it was margin leaf curl so i started watering it every 2-3 days, 50-70 humidity/ 70-80 degrees thinking i need a dehumidifier in FL and having a hard time keeping temp and humidity right , I’ve lowered the amount of light it gets and gave it more time to sleep in darkness 16/8, and i have it in coconut husk/ sphagnum moss/ per-lite. PH around 7 neutral. watering it with distilled water. using 3 bulbs for light, 2- 15 watt LED 1650 lumens each- energy efficient bulbs and 1- 25 watt CFL 1650 lumens energy efficient/ about 5000 lumens of light. plenty of air flow in closet and light breeze always on plant. feeding plant every 10 days with a natural organic plant food with over 400 beneficial nutrients its called BGI supergain started feeding plant thinking it was having a nutrient in balance. Even put some earthworms in the pot to help keep the soil rich. just when i think the plant is getting better the leaves curl even more… not sure what to do… i don’t know the name of the strain… i am also a beginner in growing any advice would be greatly appreciated. i will also add that today 10/6/15 is day 25 for my plant and it seems like the plants growth has slowed down… thanks

The pH should be about 6.5, maybe a little lower, in soil. This by itself could be your problem. In a soil-less media, it is pretty much just like hydro and should be much closer to 5.8, I’d not let it range much higher than 6.0 in a nearly pure coco/peat/perlite mix, certainly not above 6.5.

What is the EC or TDS building up in your soil/media? And what is this ‘measurement of concentration’, the EC/TDS/PPM, in your “natural organic plant food” when mixed with water to feed your plants?

Are you sure the heat from the bulbs isn’t getting the leaves too hot?


alright ill try to lower the PH a little more and the powder on the top layer on the soil is DE its a powdered shell that kills insects i put it on there as a precaution it doesn’t harm the plant… and the food i fed the plant was 1ml of food mixed into a 8oz spay bottle and you spray the plants leaves every 10-15 days

And the pH of the mixture you are spraying on the leaves?

all the bulbs hang about a foot and a half above the plant and all the bulbs produce little to no heat and im unsure of the PH of the food ive only just started feeding my plant i was already having the curling problem long before i was feeding it. i started feeding it thinking i was having a nutrient problem

It’s all important, pH of the food, the water, and even what builds up in the soil. Also the nutrient concentration, the EC or TDS of the water alone and the food mix. It all can all be making the difference.

If I had to guess, I bet you are using a high pH water, like tap water, that is likely too hard and too high of pH. Most tap water, even tap water that is not hard is around 7.5 pH, way to high, the pH will cause a nutrient problem, a “nutrient lockout”. A EC of more than 0.1 or a TDS/PPM of more than 50 PPM, and a pH above 6.5 is probably going to cause you problems.


i’ve been using distilled water

And what is bringing your pH so high?

well the PH isnt that high its a 7 on a scale of 14 so its neutral

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Again, it is high. You need 5.8 for hydro, And soil-less media is hydro.

so you want it being more base instead of neutral

No, more acid, Anything below 7.0 is acid, and cannabis is a acid loving plant.

Also, maybe try not spraying the leaves, it doesn’t seem to be helping and just confuses the issue.

alright i understand now i thought the PH should be neutral but if it needs to more acidic ill make it a little more acidic… thanks for the advice

Another thought I had, be careful you aren’t drowning the roots, cannabis also likes a very airy soil and needs lots of oxygen at the roots, not that different than cactus roots. Be sure to let the soil nearly totally dry between watering or feeding.

ok thanks for all your help ill change the Ph to make it a little more acidic and ill let it dry out more.

I pulled this off one of my plants this morning.
I can’t find my meter so off to home depot to get another one.
Do you have any advice on this Stoner or Latewood.



Well, you know me, I always want to know the pH, lol. And then the TDS. So I wouldn’t say for sure until you get your new meter. But don’t forget, some leaves, especially lower leaves or leaves not getting as much light, often the the reason they may be becoming chlorotic is not always a deficiency nor lockout nor even a toxicity, but sometimes it is just the plant determining it no longer needs that leaf and is using the stores contained inside it and then self pruning.


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That’s a good thought Stone!
So many variables…lol

By the way. I got a new meter and two plants were below 5.0 and the other two were 7.0
I have already started to fix the problems with lime and baking soda and water. Any thoughts you may have are always welcome.