Leaf yellowing problem

[ldawg]

Hi

 

Im currently flowering 2 plants in a small cupboard under a 400W HPS.

 

They are growing in soil, watered by hand, with some 'thrive' fertaliser added every now and then.

 

So far all has been going well, but now, 34 days into flower i have noticed something unusual..

 

Some of the leaves are turning yellow and darkening at the tips.

Furthermore some of the more healthy looking leaves are darkening at the tips.

Photos attached.

 

I had afew ideas from reading through the forums - perhaps overwatering, or possibly some sort of nutrient deficciency.

 

It would be great to get some opinions from the experts!

 

Cheers

[nitram]

Hi ldawg,

 

The burning & browning up-curled tips says nutrient burn - to resolve give a good flush with PH adjusted water only.

Make sure when you feeds or water the PH is in a range 5.8-6.2 (same when fulshing)

Let it dry out well .............. 48 hrs break then resume.

 

You could change your nutrients to a MJ range as the 'thrive' fertilizer is not the best to work with.

 

It appears as though the nutrients may be calusing a lock out of Nitrogen (hence fading yellow leaves)

Nitty.

[ldawg]

thanks for the advice nitty

 

I've tried what you said, with flushing and using MJ nutes, and it hasn't improved the situation

 

The girls are only afew weeks away from being ready, and im starting to worry

 

Is there anything else that you think I could try?

[biggerbuds]

i am 98% sure its underfeeding, 2% could be ph lockout but do not think so

 

i am very sure its not overwatering because leaves are standing nicely.

 

if they was mine i would feed them quickly