Need help please - Rapidly losing plant at end of flower

[Veghead]

I'm meant to be nearing the final few weeks of my grow, and I've noticed that one plant in particular hasn't really buded that well. I've thought perhaps it just has a longer life to all the other strains I have growing which are nearing the end. And now quite rapidly the upper leaves are going yellow. I thought at first it could be a magnesium deficiency, but I've tried to straighten it out but it's still progressing.
Has anyone got any ideas for me please as I'm concerned I'll be loosing the plant after a good few weeks of growing. One or two other plants have shown similar yellowing too, but they're much further on/nearing the final flush.
Thanks in advance

 

[The Germinator]

You say your flushing it? Are you letting the soil dry between? I will be watching this thread. Anxious to find out what it is.


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[Veghead]

You say your flushing it? Are you letting the soil dry between? I will be watching this thread. Anxious to find out what it is.


Sent from my iPhone using 420 Magazine Mobile App

Hi Germinator. No, not flushing it. All plants should be near the flush. But this one in particular has been really slow with the budding. It's almost completely stopped.. then the upper leaves have starting to turn yellow and die. It's happening quickly too. I did some research about 2 weeks ago when it first started to show signs and I came to the conclusion it was mag def.. but I've not been able to correct it which makes me think it's something else.
Don't believe it's a lock out either.
Unfortunately I'm feeling like it may be too late for it. My other 6 plants have done alright and are a week away from flush.

 

[dickiefickle]

over fertilization

 

[Veghead]

over fertilization

Shouldn't be man. They're on half strength nutes.

 

[Steve Green]

Throw us a little more info, pH of the soil and run off would be the real interesting thing. Have a look at the sticky on how to post in the help section for the type of information that helps.

Ph issues cause lock outs of certain nutrients which effectively cause a deficiency, but can't be fixed by simply adding more of that nute.