Potassium Deficiency or Overwatering?

jimbonorman

jimbonorman

Well-Known Member
Hey Folks, I’ve been growing these Pakistan Valley plants for a couple months now. Transplanted them to 5 gals mid December and went on vacation for 10 days around Christmas so had to use Blumats while i was gone. they started showing leaf browning/drying once I returned. I assumed it was a sign of too much/constant water so I’ve been careful not to overwater them but the growth has been slow this month and I can’t seem to shake the brown edges on older leaves - they just keep coming.

I’m prone to overwatering so I’m skeptical of my own habits, but I’m also wondering if it’s time to re-up the nutrients. They’ve only been in these pots for probably a month now and they haven’t exploded yet so I’d be surprised if it was a nutrient deficiency that started showing itself so soon (early January…couple weeks after transplant). Here’s my setup:


FFOF soil w/ perlite and Dynomyco
RH 60ish (can fluctuate from 55 to 65)
Temps: daytime 74-77, nighttime 69-71
Tap water ph’d to 6.5
PPFD 700ish

Would love to hear any thoughts or advice. Thanks!
 

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warble

warble

Well-Known Member
It looks like you're not getting enough nitrogen into them. That's why I suggested Ph 6.2. How is the humidity?
 
jimbonorman

jimbonorman

Well-Known Member
O
warble said:
It looks like you're not getting enough nitrogen into them. That's why I suggested Ph 6.2. How is the humidity?
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Oh sorry I misread your first reply. Is 6.2 better for soil? I can def aim for that - I have to lower it every time anyway.

RH is usually around 60 - 65. It did drop down to the 30s for most of the vacation duration since my humidifier ran out of water after a couple days. I guess I've been thinking it got a little stressed out during that time frame and needed a few weeks to stabilize...but this has been going on for almost a month now so I'm a bit perplexed...

I can always re-up general veg nutrients or maybe start with just worm castings to test?
 
warble

warble

Well-Known Member
If you just trans potted them, start low with the nutes. They look healthy enough to make it. So I wouldn't flip them until you get this under control. Your new growth looks okay, but I would do a worm tea next time she needs some feed. Over watering looks like the leaves are clawing downward. You don't look like that is the problem. They could have just dried out a little while you were gone. They should pick right up, now that you can monitor more close. Keep up the good work.
 
jimbonorman

jimbonorman

Well-Known Member
warble said:
If you just trans potted them, start low with the nutes. They look healthy enough to make it. So I wouldn't flip them until you get this under control. Your new growth looks okay, but I would do a worm tea next time she needs some feed. Over watering looks like the leaves are clawing downward. You don't look like that is the problem. They could have just dried out a little while you were gone. They should pick right up, now that you can monitor more close. Keep up the good work.
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Conversely, could this possibly be nutrient burn from FFOF? I did add worm castings to FFOF before I transplanted them back in mid/late Dec...
 
Cousin Bo

Cousin Bo

Well-Known Member
jimbonorman said:
Also for more visual context, here are pics of them before I went on vacation (Dec 19) and after I had returned (Jan 4)
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Your soil looks really dry. Try watering it good and not just a tiny in the center. FFOF should still have some nutrients in it if you get it wet. And there's no need to ph the water right now. The soil will buffer it. 6.2 is ok but 6.5-7.5 is better for soil anyways.
 
warble

warble

Well-Known Member
About Ph in soil, I treat my veg plants to a lower Ph around 6.1 to 6.3 and bloom from 6.3 to 6.6. I have used FFOF, but now I use plain ol' peat with a bunch of perilite. I do add some worm castings and dolomite. Works for me, but YMMV.
 
jimbonorman

jimbonorman

Well-Known Member
Cousin Bo said:
Your soil looks really dry. Try watering it good and not just a tiny in the center. FFOF should still have some nutrients in it if you get it wet. And there's no need to ph the water right now. The soil will buffer it. 6.2 is ok but 6.5-7.5 is better for soil anyways.
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Those were old pics, FYI...but I do wonder if the plants were not getting enough water with the Blumats and I interpreted that as overwatering...so I continued to under water them for a few weeks and that's why the browning of the tips has persisted?
 
Cousin Bo

Cousin Bo

Well-Known Member
jimbonorman said:
Those were old pics, FYI...but I do wonder if the plants were not getting enough water with the Blumats and I interpreted that as overwatering...so I continued to under water them for a few weeks and that's why the browning of the tips has persisted?
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Water them good and I bet that solves the problem. What do you plan on using for nutrients when it's time? You have only given water so far correct?
 
Cousin Bo

Cousin Bo

Well-Known Member
jimbonorman said:
Yeah just water so far. I use Down To Earth 4-4-4 during veg and then their 4-8-4 during flower.
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Cool. What's your tap water ph? You probably don't even need to adjust it. ph down can actually cause problems in organic soil if you use too much. It uses up your oyster shell meal faster which is one way the soil buffers itself.
 
Cousin Bo

Cousin Bo

Well-Known Member
jimbonorman said:
Right out of the tap it's just under 9, but after sitting out for a day to burn of the chlorine it settles somewhere in the 7.5 - 8 range. I occasionally use Bloom City's Clean Kelp to lower the ph but most of the time I'm using this organic crystal-looking stuff.
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7.5-8 is fine. The organic crystals are probably citric acid. You can buy a huge bag for cheap on Amazon for future reference. It also works well to kill bugs if needed. If it makes you feel better to adjust the ph you can but it's not necessary if it's around 7-8 anyways.
 
tstick

tstick

Well-Known Member
Just for fun, check the runoff water pH. I'll bet the soil is overly acidic. I run almost the same soil mix as you and this last time, my plants started to look really sick. I knew it was not a deficiency because the soil should have plenty of nutrients in it right out of the bag to last at least a month and the plants were small at the time....so I knew they couldn't be depleting the nutes. I had the General Hydroponics pH drops, so I checked my tap water pH and it was ~7.0, so I bumped it down to ~6.5. That was the incoming water. Then I ran about a gallon through the pot and let it drain into another bucket for awhile. I tested that runoff water and it was.....*drum roll*....~4.0!!! WHAAAT? "Well there's yer problem!" ;)

So I started "rinsing" the soil with several gallons of water that was pH'd UP to ~8.0 and checked the subsequent runoff water until it got into an acceptable range again. When it came time to put them int a bigger container, I went back and added some dolomite lime and some bio-char to the soil mix. That seemed to have worked perfectly because my runoff pH became consistent with the incoming water pH. All the plants bounced back to good health in a couple of weeks but I honestly thought I was going to have to trash the entire grow. I don't know why the soil pH was so low, but whatever it was, was the cause of the problems.

Anyway, sorry for the long post...-2 cent and a cuppa coffee! ;)
 
jimbonorman

jimbonorman

Well-Known Member
tstick said:
Just for fun, check the runoff water pH. I'll bet the soil is overly acidic. I run almost the same soil mix as you and this last time, my plants started to look really sick. I knew it was not a deficiency because the soil should have plenty of nutrients in it right out of the bag to last at least a month and the plants were small at the time....so I knew they couldn't be depleting the nutes. I had the General Hydroponics pH drops, so I checked my tap water pH and it was ~7.0, so I bumped it down to ~6.5. That was the incoming water. Then I ran about a gallon through the pot and let it drain into another bucket for awhile. I tested that runoff water and it was.....*drum roll*....~4.0!!! WHAAAT? "Well there's yer problem!" ;)

So I started "rinsing" the soil with several gallons of water that was pH'd UP to ~8.0 and checked the subsequent runoff water until it got into an acceptable range again. When it came time to put them int a bigger container, I went back and added some dolomite lime and some bio-char to the soil mix. That seemed to have worked perfectly because my runoff pH became consistent with the incoming water pH. All the plants bounced back to good health in a couple of weeks but I honestly thought I was going to have to trash the entire grow. I don't know why the soil pH was so low, but whatever it was, was the cause of the problems.

Anyway, sorry for the long post...-2 cent and a cuppa coffee! ;)
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Wow that's super interesting. I just watered them this morning so will give them a few days before checking the run-off.

I was running into weird issues like this last spring until someone in this forum suggested that the molasses I was adding to my waterings was lowering the ph...so I decided to ph my water after adding the molasses and it was somewhere in the 4 - 5 range. Once I stopped that they recovered. Needless to say, I'm not using molasses this run but this current issue is equally perplexing so maybe it is a ph issue after all. Thanks!
 
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