Potassium deficiency?

Sugar bomb punch entering week 4 of flower, 2x 120w LEDs living soil 4 gallon pots, suffered what looks like nitrogen deficiencies during stretch but clawing at the tops weirdly as if it had too much so no idea. Been using bloom 1 nutes from living soils but haven't used bloom 2 yet which is for post stretch period which I believe this now is. It presented as if it was nutrient burn but runoff comes out at 900 ish, it's handled way more accidentally while in veg without burn, PH in and out are always between 5 and 6, occasional molasses in the water.

PH between 6 and 7 even, been a long day

Is bloom 2 higher in K? Last pic deffo looks like clsssic K def. Leaf edges yellow then burn. Maybe should’ve introduced it a week or so earlier?

Yeah, you could go heavier PK feed.
Check the 2nd picture and compare the color of the leaves.
That bluish tint is more often than not phosphorus deficiency.
Also seems like you got K deficiency spotted out.

And for consideration, could you be getting tad too much light?
Few of the symptoms could be because of too much light.

Size of root system, size of plant all are factors in how much they can tolerate light.

240w led is too much light ? lol
900 ppm ? That's oh so high, your tips are burnt, everyone of them.
I think your starting to deal with a lockout and toxicity.
What are your temps and rh ?
What water are you using ?
Put a picture of your stems aswell.

DanKiller said:

240w led is too much light ? lol
900 ppm ? That's oh so high, your tips are burnt, everyone of them.
I think your starting to deal with a lockout and toxicity.
What are your temps and rh ?
What water are you using ?
Put a picture of your stems aswell.

Click to expand...

Well you can easily light stress a cutting with about 100ppfd 24/7.
So it definatly depends on the root system how much they tolerate before it starts to stress them.

As for ppm, it could be molecular instead of elemental so I wouldn't give it too much thought.
How do you think Potassium deficiency first shows itself? Yes, from the leaf tips.
And the telltale sign is if the margins starts to show same symptom. You can tell the difference from excess/deficiency just from the tips though.

Also the red leaf stems coupled with bluish tint on the leaves is phosphorus deficiency.

Mid plant leaves will sometimes show deficiency symptoms when getting too much light. When I returned to 12/12 after a couple years of shorter “lights on”, my plants looked horrid. I had to cut back on the power. DLI is real and those photons piled up with the added “on” time.

Grow Weed Easy has excellent info under “Plant Doctor”.

Nutty sKunK said:

Is bloom 2 higher in K? Last pic deffo looks like clsssic K def. Leaf edges yellow then burn. Maybe should’ve introduced it a week or so earlier?

Click to expand...

Yeah higher in P and K lighter in N

cage said:

Yeah, you could go heavier PK feed.
Check the 2nd picture and compare the color of the leaves.
That bluish tint is more often than not phosphorus deficiency.
Also seems like you got K deficiency spotted out.

And for consideration, could you be getting tad too much light?
Few of the symptoms could be because of too much light.

Size of root system, size of plant all are factors in how much they can tolerate light.

Click to expand...

Possibly, the plants are 24" or more away from them but almost full power, they did suffer slight light stress a while back but it hadn't returned in the time it was pre flower and going on stretch

DanKiller said:

240w led is too much light ? lol
900 ppm ? That's oh so high, your tips are burnt, everyone of them.
I think your starting to deal with a lockout and toxicity.
What are your temps and rh ?
What water are you using ?
Put a picture of your stems aswell.

Click to expand...

This one accidentally sat in almost 3000 just before flip, the rest told me about it but this one didn't care, probably would've been fine without a flush temps mid to high 70 rh 50 to 60, spring water ph'd to 6.5. Will get stem pics soon yeah they are reddish

Ok so too high ec fosure, you are burning them, the K def that cage said is caused by toxicity not by not giving enough K.
Burnt tips are not K def symptom, if they are burnt on the whole segment of the leaf then yes it's K def.
You have both of those symptoms but it's not cause you under fed that's what I'm trying to say.
If your stems are reddish aswell, you are in a lockout/toxicity.

cage said:

Well you can easily light stress a cutting with about 100ppfd 24/7.
So it definatly depends on the root system how much they tolerate before it starts to stress them.

Click to expand...

The op plants look like cuttings to you ?

DanKiller said:

Ok so too high ec fosure, you are burning them, the K def that cage said is caused by toxicity not by not giving enough K.
Burnt tips are not K def symptom, if they are burnt on the whole segment of the leaf then yes it's K def.
You have both of those symptoms but it's not cause you under fed that's what I'm trying to say.
If your stems are reddish aswell, you are in a lockout/toxicity.


The op plants look like cuttings to you ?

Click to expand...

Lol, did I say OP's plant are cuttings?
Big difference with lockout and toxicity.
Which nutrients you think are locked out and which are in toxic amounts?

cage said:

Lol, did I say OP's plant are cuttings?
Big difference with lockout and toxicity.
Which nutrients you think are locked out and which are in toxic amounts?

Click to expand...

It was an odd one, it seemed bottom leaves clearly suffered N deficiency but were clawing at the top leaves