White Widow fan leaves and colas turning brown... :(

MidnightJoker

Well-Known Member
I am currently on day 47 of 70 days flowering my White Widow. I am growing 2 plants currently. One of the plants looks completely fine, while the other one is turning brown on the fan leaves and the pistils on the colas.

I am using Fox Farm trio of nutes for flowering and Epsom Salts in case this was a cal/mag deficiency. I suspected it might be a fungus as well, but I see no sign of browning in the colas or at the base of the fan leaves to the buds. It is completely green.

Please help me diagnose what the problem might be as I only have 2 weeks left of flowering and I don't want to lose one of my plants. Thanks for any advise.
 

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cannabineer

Ursus marijanus
Since the plants look otherwise so healthy, I doubt it's a deficiency. It's all near the tops ... could it be heat stress? What temps and lighting? cn
 

MidnightJoker

Well-Known Member
Yeah, I don't think it's heat stress. My other White Widow is looking fantastic and it's right next to the WW that has problems. I am using a 400w HPS, temps are pretty much a constant 79F. But I have been having humidity problems in the tent. I have been doing my best to keep it in the 40% range, but some days it has gotten to 60% RH. Not sure if that could be it.
 

cannabineer

Ursus marijanus
No, 60% should be fine. I'm stumped. The good news is you're within 2 weeks of harvest ... might be able to just ride it out. Lovely plants over all; my compliemnts! cn
 

cannabineer

Ursus marijanus
Not boron for sure. Boron deficiency leads to a very diagnostic die-off of growing tips, and those growing tips are healthy. I was thinking "could it be lack of P, possibly compounded with K def?" but after spending some time in Midnight Joker's grow journal I can't see how that would be. Jmo ... cn
 

MidnightJoker

Well-Known Member
Not boron for sure. Boron deficiency leads to a very diagnostic die-off of growing tips, and those growing tips are healthy. I was thinking "could it be lack of P, possibly compounded with K def?" but after spending some time in Midnight Joker's grow journal I can't see how that would be. Jmo ... cn
Thanks. That's why I am stumped as well. It is definitely not a fungus or mold, but I am not sure what could be causing one of my plants to go south on me. I am giving Epsom Salts in addition to a regular dosing of Big Bloom and Tiger Bloom.
 

cannabineer

Ursus marijanus
This is an extra super long shot. However - I rec'd my Secret Jardin 4x4 about a week ago, and after being set up for that week it still stinks of plasticizer. I noticed that you moved your grow into a new unit of the same model. Recently I read something that rocked my world ... about a batch of bad vinyl tubing that leached out a dibytyl phthalate plasticizer that proved to cause Mystery Ailment (yellowing leaves and general failure to thrive) in Cannabis ... severe enough to kill some commercial grows that were otherwise dialed all the way in.
I wonder if your plant, the extra susceptible one, is showing a touch of plasticizer toxicity. How is it located relative to your filter intake? Lol, I'm obviously grasping at straws here. If it IS that ... the good news is that by your next grow all that plasticizer will have evaporated off. cn
 

MidnightJoker

Well-Known Member
Huh, I never thought it could be tent related. The one plant that is thriving is the one that is directly below my carbon filter, while the plant that is not doing well is about a foot away. Should I try and switch the plants in the room? Do you think that will make a difference?
 

cannabineer

Ursus marijanus
Can't really tell you ... like I said it's a five-hundred-yard shot with iron sights. My instinct however is just stay the course. It's probably a sensitive pheno if my plastic theory has any merit at all. As far as i can tell from your journal, you're hitting all the bases. cn
 

max316420

Well-Known Member
Looks like your calcium is getting locked out, If your 2 weeks from chopping then I would feed with just plain water. I grow ww and I have noticed that in soil you have to supplement with calmag right when you flip your lights to 12/12. Nice looking ladies tho
 

MidnightJoker

Well-Known Member
That is some great info about having to supplement the WW with cal/mag right away when I flip. +rep...I will keep that in mind for my future WW grows. I am actually going to flower these until about 10 weeks, so I have 3 more weeks to go. I will cut off the feeding after the 8th week is done. Thanks man for the help.
 

Devilspawn

Well-Known Member
Check your Ph and PPM of your feed soln. It does look like lock out of Cal/Mg which can happen with salt build up or pH being out of whack. Had it ahppen in my grow when pH crashed while I was away- bring it back in line plus epson salts or cal /Mg which you are using helped. Too high a nute buld up may do it too... plain pH water with a little Cal/Mg might be a good call.
 

MidnightJoker

Well-Known Member
Thanks, for the advice. +rep. I know it's not the PH because I always balance to 6.5-7.0. But I think you may be on the right track with a salt build up from the nutes. I am planning on giving it a flush today with Sledgehammer. Hopefully that will help out.
 

420Trix

Member
That lady looks fine to me. Dont some plants change colors (purple, blue, yellow, red, etc.) towards the end of flowering? Also, you stated you were on day 47 of 70 and two weeks from the end...my math says you have 23 days left...and the last 2 weeks flush with water only
 

ATL HYDRO

Active Member
These guys are correct, most plants have yellowing leaved near the end of flower because the plant is pulling all energy out of the leaf inb a last ditch effort to swell the buds and get pollenated. It is safe to say you have nothing to worry about, those WW colas look awesome!
 
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