Can't tell what deficiency this is, and it's spreading fast. Help!!!

Hello all. I have a Blackjack plant that has about a month left in flower. The leaves have begun an awful yellowing at the veins of the leaves then eventually kills the leaves. It is only affecting lower/middle leaves. What do the pros have to say about this, as far as diagnosis? The first pic is at an earlier stage of the issue. Second shows the progression..IMMENSE thanx in advance for any help!!!

View attachment 2230235View attachment 2230236

the lower leaves of your plant are not getting as much light as the upper parts. so they start to yellow.

Thank you for the esponse, david! Definitely an interesting theory as it was pretty bushy towards the bottom (until the leaves started dying like this). It's odd though, because I have lights at the bottom of the pot as can be seen in my other post about this grow a while back (which never took off, so I let it die). https://www.rollitup.org/cfl-fluorescent-lighting/527963-3rd-grow-nirvanas-blackjack-229-a.html#post7427353

Would anything else cause this type of yellowing?

Well some people say that it is a natural part of growing process. But if your plant stops growing as a whole AND at the same time has yellowing lower leaves I would definitely start to worry. I hope it's not the case with you. best of luck brother !

I'm just concerned that at the rate it's going, it's not going to make it through this last month! I believe there are just 3 nodes of big fan leaves left, and some of the smaller leaves at the bottom and liiittle in the middle are getting it now. With such a loss/reduction in the ability to absorb light(fewer leaves), I would think that the yield is going to suffer.

If I had to "guesstimate", at the rate it's yellowing and leaves are falling off, it will fall about 2 weeks short of the proper finishing time. And as we all know, those last few weeks are prime and crucial bud-plumping/compacting time.

Anyone else have any thoughts?

about week 4 or 5 you will get some die off and again at the end week 8 or 10 most of the time. what are you using for nutrients? what kind of soil or medium are you using? do you know your ph? how long have the plants been in those pots?

I would do a transplant into a bigger pot and bust the root ball up a little just enough to wake it up.also put a fan on it you need a slight breeze. did you know over watering can cause yellowing?are you letting your pots dry out before you water?

ismokealotofpot:

MEDIUM: FF OCEAN FOREST

NUTRIENTS:during second month of veg=MIRICALE GROW 1/4 strenght (MG... I know) after the first 3 weeks of veg, and up till I switched to 12/12, Been using FF Cha-Ching at half strength since the 3rd week in flowering. And ANY time I use nutes, it's always every other watering at the most. ph of water is always adjusted to about 6.5 (using liquid test, don't have digital).

PH: As stated, water is always adjusted to 6.5. Run off tested at between 5.5 and 6 with the last watering. I don't overwater, and always wait until the medium is very dry before watering.

POT RESIDENCY: Since 3 weeks after breaking soil. I transfered it into the 3 gallon pot it's in from a small (pint, I think?) pot I used to start it out in. What concerns me though with transplanting is all the risk i read about concerning shock and it going hermie as a result. I have never transplanted at this stage (or size: 2 1/4 feet tall), so I do have concerns of error.

And I do have three 120cm pc fans going on it for a breeze.

What concerns me is not so much the yellowing of the leaf, but it looks like a lot of wilt in all the leaves in the pic. How far up does this wilt go? I am thinking the roots are struggling under too much water, not enough oxygen, or too much salt.

Nitegazer:
The wilting is very minimal, and does not go up far at all (maybe just breaching the middle section) and is only on a sme leaves here and there. And I don't believe it would be too much water or no enough oxygen, due to waiting until it's dry to water, and drainage is superb from what I can tell. Although the salt concern could have some validity to it, since i have been using solubles for nutes.

What say you, Sir ismokealotofpot, after info has been provided?

I don't think transplanting will hurt you if the roots get all balled up then they cant take up nutrients and it will cause lockout. if its budding put a trash bag around it so you don't get soil on your nugs. chaching is 1/4 teaspoon per gallon. i see nothing wrong with the mg fertilizer either I use mg 20 20 20 for vedge at full strength half teaspoon per gallon no calmag for vedging plants . you will need cal-mag plus for flowering plants about half teaspoon per gallon. stop skipping feedings and use full strength or real close.that's my two cents

make sure you have enough head room for a transplant. when or if you pull it out of the pot take a look at the roots and see if they are brown or white. also if they are circling the pot you will need to bust them up so they stop circling the bottom and grow down and out.