Problem identifying nutrient deficiencies or over fertilisation

[MadMac]

Hello,
as the titel suggest... i'm not sure...
So today i visit a good friends grow room...
He is 7 weeks in flower now and have some trouble...
So first as i saw the plants my diagnose was over fertilization.
But he told me that he give only give little organic bloom... nothing else... his soil was always good so i took some leaves and @ home i compared the leaves with images i found over nutrient deficiencies...
Now it looks to me also like potassium deficiencies late stage but i'm not sure... can it also be over fertilization? The plants where i took the leaves are from Golden Tiger cut...
here the leaves:

many thx
M

 

[Scrappy-doo]

Looks like nute burn to me. The base of the leaves looks real dark and texture looks bubbly. How does the rest of the plant look? Either way, at 7 weeks not much time to do a whole lot about it.

 

[MadMac]

thx Scrappy-doo,
well the plant looks overall ok but you can clearly see the issues in some leafs...
flowers are fine no fox tailing ...
so my advise was next 7 days only clear water... and well next visit i will measure ph & ec.
Maybe it gives me more info... if nute burn than it must be a high ec level?
thx
M.

 

[Scrappy-doo]

I would assume so. If your buddy only gave a little bloom food I'd be on the fence on that as you were, but "a little" isn't specific enough. It could be a deficiency in advanced stages but there would have been signs earlier. Could be nutes have just built up in the soil if he doesn't water till runoff. Or maybe what he cconsidered a little bloom food was actually a lot. Hard to say just based on a couple pics of leaves and not knowing the routine. I'd be asking for details on the feeding and how suddenly this came about. If they were fine one day and then a day or 2 after the last feeding looked like that well then the answer is pretty obvious. This far along though, and I'm assuming they are standard 9 or so week strains, I'd probably just feed a moderate amount with runoff until they start the flush cycle. Hope it works out.

 

[dubi]

Hi MadMac,

Looks like a sign of excessive salt concentration, lack of ventilation, too much moisture or a combination of these and/or other factors.

We need more info about the growing conditions for a more precise answer: temps, ventilation, fertilizers, ph and ec in the waterings, any change made since that the problem appeared, etc ...

 

[dubi]

Hi MadMac,

Looks like a sign of excessive salt concentration, lack of ventilation, excessive distance between waterings, too much moisture or a combination of these and/or other factors.

We need more info about the growing conditions for a more precise answer: temps, ventilation, fertilizers, ph and ec in the waterings, any change made since that the problem appeared, etc ... an overall pic of the plant would also help.

 

[Redbuddz]

Hey MadMAc

the 1st problem with pinpointing over fertilization and/or nutrient deficiencies is it almost always more then just ONE nutrient and/or problem that exists. the 2nd problem comes when people think they know and then over compensate and it just makes things worse.

like a few of the folks here have suggested is could be a salt issue, it could be a PH problem or it could be over/under fertilization.

Sounds like you're too far into flowering to really correct this issue so I would really scrutinize your methods and try to pinpoint your mistake so that it does not happen again

Good Luck MM

Keep on Growing Ya'll


Redbuddz

 

[MadMac]

high,
many thx for all the comments!
well just after my work i drove with my equipment (EC, PH Meter) to my friends grow room.
I tried to explain him that i need pic's from the plants but he has too much paranoia... :-(
So after drink a beer and smoke a good Malawi he told me that he used also some nettle tee that he made for his tomatoes ... he used Canna terra flores also... but he mention that he uses less than stated on the packaging...
So here are the results:
PH from his rain water is 6.7
EC from his rain water is 0.25

PH test from his soil is 6.4
PH test from drain water 6.5
1 EC test flush with rain water 12l 7.4 !!! taken from drain water
2 EC test flush with rain water 12l 3.2 !!! taken from drain water
3 EC test flush with rain water 12l 1.0 taken from drain water

So after the first result i thought i'm too stoned and the device is broken... but i did a test with distilled water and it had EC 0... and the Rain Water 0.25... so i was shocked... !
That's why i did the flush... hope the plants will recover... he has one Golden Tiger and Malawi cut from me and Bubblegum XL and a other dutch hybrid... the dutch hybrids are close to harvest... maybe 2 weeks so nothing to do as to flush... maybe a second time in 6 day's... ?
So what to do with his sativa's? Flush them also and then wait and see or better do nothing?

The grow room has following specs:
Grow tent 120x120x200
Temp @ day around 26°C night 18°C
very good vent system... it's from me ;-)
He use a 600w HPS with cool tube... distance to plant around 40-50cm...
So the ACE genetics looking ok to me... so nice bud's are coming but also some tip burn on the bud leaves... not much but some.... older and bigger leaves have more damage... looks like they can survive... but what to do?
The dutch hybrids are looking not good @ all... most leaves are brown also on most bud's... so not much to do as to flush and hope they will taste not to bad...
any help is still welcome... because he is a good guy... but has no green thumb ;-)
thx
M.