HELP! Lower leaves turning yellow

[Custom45]

Hi I'm currently flowering a mother plant, in week 5 of flowering, since week 1 been having trouble with lower leaves turning yellow. They eventually wilt, go brown curl up and die. Usually they pull off easily. Lost quite a few this way and the problem is working its way up to the top leaves.

I read about nitrogen deficiency so have been feeding extra nutrients, including calmag supplement, but problem still persists.

Leaves start to turn yellow at the stalk and spread down leaf. Not had this problem with the regular plants, is it because it's a mother? Any help much appreciated.

Growing in coco
600w led

Feeding 5l water every 2 days with
-20ml Canna a+b,
12.5ml Cannazym,
7.5ml pk 13/14
20ml Cannaboost,
5ml CalMag supplement

pH water to around 5.5-6.0 after adding nutrients
Around 21-15⁰c and 45-55% humidity

Early stage of yellowing


Later stage. Some leaves turn much yellower, then turn brown, shrivel up and die

[Custom45]

Forgot to add.. been doing a foliar spray a few times with nitrogen, CalMag and Cannaboost, but it's not really helped.

[Tersky]

Wait, foliar spray on flowering plant? I dont think that is causing your issue but that is a recipe for bud rot IMO.

[Gingerbeard]

How to Stop Flowering Stage Nutrient Deficiencies | Grow Weed Easy

[JeffInCanada]

Hi Custom45
Does any of your nutes or supplements have Sulfur in them? Just a guess.

https://www.growweedeasy.com/cannabis-plant-problems/sulfur-deficiency

[DeadlyFruit]

I am not typically a fan of foliar sprays beyond pest control but I can’t honestly say if I have a bias or if there is anything negative about it. With that said I think it more likely a pH problem triggering nute deficiency(s). How do you measure your pH? If you use a digital pen type device, when did you last calibrate it and what is the pH of your runoff water? I learned the hard way how far off a pH tester can slip without regular calibration (every few weeks is probably enough depending on the device and how you use it).

[Gingerbeard]

Hey, y'all. The clue is being in week 5 of flowering. Any nutrient issues, at this point, are common. They are in the autumns of their lives and are turning color as some plants do. Any discolored or damaged leaves will fall off. Don't fret. Since you're in mid-late flowering, your plants are more concerned with flower development. I don't know the nutes you're using. Are they veg of flower nutes?
Foliar sprays are great for vegging, not so much in flowering. One, the same issue with regular feeding: your plant doesn't care about fan leaves. Two, it's not good to get foliar spray on your buds. The moisture can cause mold and rot and junk, and you don't want nute residue in your buds.
I've never dealt with sulfur issues. The link JeffInCanada provided says sulfur issues appear in new growth. JIC's issues are starting low and working their way up.

Can you get a picture of the whole plant Custom45 ?

[homegrown]

I would try increasing your ph to around 6.2- 6.3. I grow in coco/perlite and 6.2 is my base, i'll fluctuate a bit from there but try to stay above 6. https://www.growweedeasy.com/ph#hydroponic-soilless-pH