Leaves are falling off! ~3 weeks left in flower

Hi all,


I have noticed a potential problem with my flowering plants. This is my first grow so I am a bit underexpierenced. The first thing I noticed was that the very edges of the leafs were turning up and changing into a dark brownish color. Then the main leaves on the plant began to turn a very pale yellowish green and have begun to fall off. I have not changed anything in their environment. Have been maintaining RH around 40-50%, temps in the mid to low 70's and have not noticed a bug or mold/mildew problem.

This started occurring about 3 weeks or so into flowering and as of right now I have about 3-4 weeks left and the colas are looking AMAZING so I'm not sure if this is the plant just doing it's thing and focusing it's energy to its Colas or if this is a real problem. Has anyone experienced this before and what can I do to correct it if its a problem?

I attached one photo from a few days ago showing the edges of the leaves turning up. If you think a pic of something else would help figure out whats going on let me know and I can post more.


Thanks for taking a look.

My plant is just a little further along than yours and I had the same issue... I think. Some of the leaves were yellowing further down towards the middle and the leaves on the colas were turning almost purple and then curling up at the edges. I upped the P & K a little and the color stopped spreading, but I don't think it's a huge issue, unless your pH is off.

Its a little late to worry now imo.
By the time you straighten out the issue it will be time to flush.
So I wouldn't worry to much about it.

I'm a bit obsessive and although I only use color drops to test Ph and dont have an exact number I always use the same, quality sourced, RO water to water my plants. The Ph shows to be within the 6.0-6.5 range and the ppm is under 400. So I can't imagine its the problem.

As far as the n-p-k, I use very rich soil in combination with a biodegradable soil tablet that helps keep the levels of the nutes up. Now the one thing I could see being a problem is that I really didnt put enough soil in the bucket, its a 3 gal bucket and there is an excess of 2-3" between the top of the bucket and the top layer of soil and can see a few inches of air pruned roots that had tried to grow so maybe thats my problem. Anyways with how close they are to harvest I dont want to change anything and kill my plant, I'd rather have some leaves fall off and keep these amazing looking Colas.


I'll put some more pics up tonight before I clean up so you all can see the actual leaves and will also post a new pic of the colas.


Thanks for the quick reply

Its what they do.
Cannabis is a annual or short-lived perennial.
They do there thing and die in nature.

Yellowing at the flowering stage is common because the plant uses extra nitrogen to produce its cola. Almost so that you find people avoid using nutes in flowering that have 3 or above n. You can pull the dying sickly so the plant doesn't stress trying to keep them alive or just wait for them to fall off. you want to concern yourself with the top three layers including the canopy and the colas. the bottoms tend to get used to feed the buds and they tend to get minimum light impact. When I found this happening I added some 6500k flouro for side branch lighting...

homegrwn, thanks for your suggestion. Got me thinking and next time around I am going to add some side lighting to help. here are some more pics, the pistils have now all started turning color and the colas have really started to fill out. Looks to be nature just doing its thing. Thanks again.