Sour crack leaves yellowing

Yardie-boy

Yardie-boy

Member
hello all. Having a few problems with my Mephisto sour crack ladies.
Week 5 from seed today and the leaves are yellowing slightly and have rusty spots on some of the others.
Currently in Coco 20L airpots watering 4 litres each every two days
Canna coco A+B at an EC of 1.2, PH 6
20-4 light cycle temp 25-27 rh 55
Any ideas what could be causing this?
Am going to start adding canna boost from next week.
Cheers all,
YB

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Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
the yellowing looks like mag deficiency, which could either mean you just need to give them a little cal-mag, or it could mean your ph is off, mag requires at least 6/1 ph to be absorbed. a lot of people say coco is hydro, but its not really, and you can't run it at 5.8 or you'll get that yellowing for sure.
that leaf cupping is only caused by a couple of things i'm aware of, either low ph, which doesn't sound like the case, or heat stress, which shouldn't be the case either.
i would drop my regular feed ppm a little, make it up with cal mag, and raise my ph to 6.2 for a couple of feedings. if that doesn't make any improvement, then i'd start thinking about other things...
 
A

Anothermeduser

Well-Known Member
So 12 from seed, looks like around 4 weeks into bud, looks like it is a bit starved, cal mag comes of spotting through the leaves on lower leaves in my experience not a general yelowing then discolored tips, i would take note and feed heavier next time, any boost you try to give them will lessen your burning quality now, looks like your on the homstretch with about a month to go, id do a bit more food then water straight for a few weeks and done.. it will be starting to yellow naturally but its a bit early, that and the leaf tips say to me underfed. Get it done and try again
 
OldMedUser

OldMedUser

Well-Known Member
If those leaves will crack when you bend them then they have toxic salts buildup in them. Likely too warm or affected by the radiant heat so draw a lot more water thru them in an attempt to cool off drawing excess nutes into the leaves and leaving the salts behind when the water goes. The turn up and burning n the leaf margins is clue #2 to excess salts.

Give them lots of water but back off on the nutes. The leaves with salt overload won't recover but by limiting nutes you won't make it worse. I've had the same problem with my plants due to low RH in the north here. Last grow I fed at half what I normally would and it went much better. Still need to find the sweet spot but on the right track now.

Good luck!
 
OldMedUser

OldMedUser

Well-Known Member
If it were Mg deficiency you'd be seeing a lot of chlorosis in the lower older fan leaves as it's a mobile nutrient and the tops will steal it from the oldest leaves first and from the bottom up the leaves will go yellow and limp. Low Ca and you'll get freckling in the mid range leaves, very dark foliage and some distortion and/or damage in the growing tips. Slower bud growth in this case.

Could be Ca but I doubt it.
 
Dabber68

Dabber68

Well-Known Member
OldMedUser said:
If those leaves will crack when you bend them then they have toxic salts buildup in them. Likely too warm or affected by the radiant heat so draw a lot more water thru them in an attempt to cool off drawing excess nutes into the leaves and leaving the salts behind when the water goes. The turn up and burning n the leaf margins is clue #2 to excess salts.

Give them lots of water but back off on the nutes. The leaves with salt overload won't recover but by limiting nutes you won't make it worse. I've had the same problem with my plants due to low RH in the north here. Last grow I fed at half what I normally would and it went much better. Still need to find the sweet spot but on the right track now.

Good luck!
Click to expand...
I was wondering about the low RH. Mine hasn't reached above 60% and that was when we had a heat wave. It generally stays between 40 and 28. So low RH can cause this Thx for sharing that info
 
OldMedUser

OldMedUser

Well-Known Member
Dabber68 said:
I was wondering about the low RH. Mine hasn't reached above 60% and that was when we had a heat wave. It generally stays between 40 and 28. So low RH can cause this Thx for sharing that info
Click to expand...
I've had problems for years with crispy leaves usually starting around week 4 or 5 in flower and sometimes progressing into the tiny bud leaves. Thought it was due to overfeeding N so got 3 part nutes to better control N levels but still had problems. My last grow I just lowered all nutes by half and the plants grew great and had soft leaves as tehy yellowed near the end. Growing in a 50:50 mix of ProMix HP and ProMix potting soil that has organic nutes added. Feeding 3-part AN nutes at lower levels.

RH in my room is often below 20% during the winter and adding with humidifier doesn't help much as my controller kicks in the fan when the heat goes up and all the moist air gets blown out. Would have to have lots of moisture in incoming air to maintain proper RH steady and that would be hard to do. Or run sealed room with CO2 and that's hard to do with such limited funds.

So just going to run lower PPMs for now on. Starting DWC tubs soon and will be experimenting with various levels but likely 500 - 600ppm max where I would go up to 1400 depending on strain. I've done DWC in tubs since 2001 so got all the other bugs worked out.

Did you try bending leaves to see if they broke where they were brown?

:peace:
 
Dabber68

Dabber68

Well-Known Member
OldMedUser said:
I've had problems for years with crispy leaves usually starting around week 4 or 5 in flower and sometimes progressing into the tiny bud leaves. Thought it was due to overfeeding N so got 3 part nutes to better control N levels but still had problems. My last grow I just lowered all nutes by half and the plants grew great and had soft leaves as tehy yellowed near the end. Growing in a 50:50 mix of ProMix HP and ProMix potting soil that has organic nutes added. Feeding 3-part AN nutes at lower levels.

RH in my room is often below 20% during the winter and adding with humidifier doesn't help much as my controller kicks in the fan when the heat goes up and all the moist air gets blown out. Would have to have lots of moisture in incoming air to maintain proper RH steady and that would be hard to do. Or run sealed room with CO2 and that's hard to do with such limited funds.

So just going to run lower PPMs for now on. Starting DWC tubs soon and will be experimenting with various levels but likely 500 - 600ppm max where I would go up to 1400 depending on strain. I've done DWC in tubs since 2001 so got all the other bugs worked out.

Did you try bending leaves to see if they broke where they were brown?

:peace:
Click to expand...
  1. Here's a leave from plant was told cal mag so flushed and gave good round of cal mag till week 4 of flower than stopped, I grow in soil and my ph is stable. ck out my 1st grow maybe you can tell better by looking. https://www.rollitup.org/t/1st-grow.951703/ I was also told that it was Crop King genetics Thx
 

Attachments

OldMedUser

OldMedUser

Well-Known Member
Now that leaf is definitely salts buildup.

Checked out your 1st grow and other than the one WW didn't see too much in the way of salts buildup. Nice grow!

If you are using real dirt with dolomite etc in it you shouldn't even need additional CalMag. I've always used only RO or distilled water and never even had CalMag until a few years back and never saw ant low Ca problems even in DWC where the only Ca they got was from the AN nutes I was using. Did see low Mg and treated that with Epsom salts and not much of that.

I see so many posts where people chime in with , Add CalMag and all your problems will magically go away when I can see there are other issues than CalMag. It's not the magic bullet some people think it is and overuse will just make things worse if there are problems.

With DWC I only change nutes once right after the stretch then go with Lucas formula to lower N levels and use Big Bud to boost flower and resin production from a week before I flip to flower. I've done around 50 tubs and a couple hundred plants in DWC and lots more in soil/soilless pots too. I'm shit as a dirt farmer but we all have our niches and mine seems to be DWC.

Tap water, especially hard water, will leave it's minerals in the soil after the plant uses the water so every time you water it builds up in the soil like the scale in a kettle does. Doing the 20% runoff each watering helps a bit but not enough if the water is hard. Town water here is around 360ppm depending on season and has a host of other minerals that can mess with your plants. At least they use chlorine instead of chloramine and stopped adding fluoride around 2006. We buy RO water for drinking as we get our water from a dugout on my property and it's like town water minus the chlorine but add in runoff farmer pollution. Got frogs and little fish in there so it must be fairly good water. My dog lived to almost 17 and he drank it every day of his life.

I found a great spot to download FREE POT BOOKS. I downloaded a grow bible first and got lots more. Books look great and complete like the real ones I have here. No web site but just a page of links. Just right click on what you want and then "Save Link As" to download so they don't open first as some are 50+ megs. They got lots. Enjoy.

:peace:
 
Dabber68

Dabber68

Well-Known Member
OldMedUser said:
Now that leaf is definitely salts buildup.

Checked out your 1st grow and other than the one WW didn't see too much in the way of salts buildup. Nice grow!

If you are using real dirt with dolomite etc in it you shouldn't even need additional CalMag. I've always used only RO or distilled water and never even had CalMag until a few years back and never saw ant low Ca problems even in DWC where the only Ca they got was from the AN nutes I was using. Did see low Mg and treated that with Epsom salts and not much of that.

I see so many posts where people chime in with , Add CalMag and all your problems will magically go away when I can see there are other issues than CalMag. It's not the magic bullet some people think it is and overuse will just make things worse if there are problems.

With DWC I only change nutes once right after the stretch then go with Lucas formula to lower N levels and use Big Bud to boost flower and resin production from a week before I flip to flower. I've done around 50 tubs and a couple hundred plants in DWC and lots more in soil/soilless pots too. I'm shit as a dirt farmer but we all have our niches and mine seems to be DWC.

Tap water, especially hard water, will leave it's minerals in the soil after the plant uses the water so every time you water it builds up in the soil like the scale in a kettle does. Doing the 20% runoff each watering helps a bit but not enough if the water is hard. Town water here is around 360ppm depending on season and has a host of other minerals that can mess with your plants. At least they use chlorine instead of chloramine and stopped adding fluoride around 2006. We buy RO water for drinking as we get our water from a dugout on my property and it's like town water minus the chlorine but add in runoff farmer pollution. Got frogs and little fish in there so it must be fairly good water. My dog lived to almost 17 and he drank it every day of his life.

I found a great spot to download FREE POT BOOKS. I downloaded a grow bible first and got lots more. Books look great and complete like the real ones I have here. No web site but just a page of links. Just right click on what you want and then "Save Link As" to download so they don't open first as some are 50+ megs. They got lots. Enjoy.

:peace:
Click to expand...
Yeah that 1 WW started out fast and ended up the runt. I didn't do enough homework b4 I started. I have another grow that is gonna start a Kush comparison and adding Azomite, Domolite, and Roots Organic to the soil along with Mykos. Gonna use 2 nute lines FF Trio liquid and powder for flower and GH Maxi to compare these 2. I will ck the FREE books out many THX
 
Yardie-boy

Yardie-boy

Member
A522672D-9692-4DF4-995B-3048B919D458.jpeg Cheers for the replies. I calibrated my PH pen and it was a whole 1 point off, so I’ve been watering at around PH 5 for the past few weeks by the looks of it ☹
The yellowinh and rusty spots are probably down to a deficiency caused by nutrient lockout due to the low PH
I gave them a flush of plain PH 6 water and
now a daily feed of PH 6.2 EC 1.3 with AB and canna boost.
They are starting to green up nicely and the buds are frosting up. 3 weeks left from Saturday so hopefully they fatten up nicely between now then.
Thanks again
 
xtsho

xtsho

Well-Known Member
Yardie-boy said:
View attachment 4058005 Cheers for the replies. I calibrated my PH pen and it was a whole 1 point off, so I’ve been watering at around PH 5 for the past few weeks by the looks of it ☹
The yellowinh and rusty spots are probably down to a deficiency caused by nutrient lockout due to the low PH
I gave them a flush of plain PH 6 water and
now a daily feed of PH 6.2 EC 1.3 with AB and canna boost.
They are starting to green up nicely and the buds are frosting up. 3 weeks left from Saturday so hopefully they fatten up nicely between now then.
Thanks again
Click to expand...
I was going to say to check your PH. I just went through the same thing with my PH pen being more than a point off before I realized it. Bought a new pen immediately. Problem solved. At least for me.
 
OldMedUser

OldMedUser

Well-Known Member
xtsho said:
I was going to say to check your PH. I just went through the same thing with my PH pen being more than a point off before I realized it. Bought a new pen immediately. Problem solved. At least for me.
Click to expand...
Most people don't take proper care of their pH pens and after a year they need new ones. Do a little research into the proper care and feeding of that sensitive scientific instrument and they can last for 7 or more years.
 
Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
xtsho said:
I was going to say to check your PH. I just went through the same thing with my PH pen being more than a point off before I realized it. Bought a new pen immediately. Problem solved. At least for me.
Click to expand...
most of them are adjustable. to keep them in real ship shape, get a bottle of 7.0 solution and a bottle of 4.0. if they are both on, you know you're accurate. if you can't reconcile both, then its time for a new unit
 
andy s

andy s

Well-Known Member
Anothermeduser said:
So 12 from seed, looks like around 4 weeks into bud, looks like it is a bit starved, cal mag comes of spotting through the leaves on lower leaves in my experience not a general yelowing then discolored tips, i would take note and feed heavier next time, any boost you try to give them will lessen your burning quality now, looks like your on the homstretch with about a month to go, id do a bit more food then water straight for a few weeks and done.. it will be starting to yellow naturally but its a bit early, that and the leaf tips say to me underfed. Get it done and try again
Click to expand...
yellowing between the veins are also a sign of a calmag def sometimes a ph flux too
 
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