Lower leaf yellowing, deficiency?

[GreenFingaz]

Soo guys I got in touch with biobizz about testing the ph for there Lightmix medium.... this is what they said

 

[GreenFingaz]

Soo guys I got in touch with biobizz about testing the ph for there Lightmix medium.... this is what they said

I got mixed messages from that response lol they're basically saying you don't have to because the microorganisms are doing there thing but you should do it anyway lol

 

[Weffalo]

Soo guys I got in touch with biobizz about testing the ph for there Lightmix medium.... this is what they said

@GreenFingaz Wow thanks so much mate, that's great info.

So my PH comes out around 5.9 with the current mix, everything does look okay with these feedings but it sounds like I should be upping the ph and maybe things will look better, I hate altering PH though because I'm only mixing 3L a time and it's so easy to go too far and have to correct

I got mixed messages from that response lol they're basically saying you don't have to because the microorganisms are doing there thing but you should do it anyway lol

Yeah after re-reading what they said I think they actually answered the question of "What ph should my nutrient mix be with BioBizz nutrients" and not something about the soil mix?

Seeing as the plant is actually looking happy for once I'd guess that the current ph has been fine, from start to finish it's been 6.3 - 5.9 depending on what I'm mixing in which for T.A nutrients is correct, hopefully the soil doesn't require any specific adjustments.

 

[GreenFingaz]

I hate altering PH though because I'm only mixing 3L a time and it's so easy to go too far and have to correct

I know the feeling .

 

[Weffalo]

Few further damaged leaves this morning, all from under the canopy, tagged leaf still okay and I'm feeling like the green at the very top of the canopy is looking a bit darker in the middle more like it should.

Leaves at the top all seem to be praying for another day in a row

Removed the two worse looking leaves but left a few on that are showing signs to see if they get worse, these leave pics are took in natural light so the colours are accurate for once. I don't know is this is still signs of defiency or if these leaves under the canopy will naturally be used for resources regardless now? I imagine they don't get much light.

 

[bluter]

nice defol.

the top shots still have the plant looking underfed to me. a lights off shot to get the true color of the tops would be a good idea. i think the light could be washing it out.

 

[cbdhemp808]

This shot from a week ago tells a story...

New growth at top of canopy is pale green, while lower down is dark green. Some lower leaves going yellow. I read this possibly as... transition to flower nutes took place, and then there wasn't enough nitrogen. The plant started stealing nitrogen from the lower leaves.

@Azimuth is a SIP grower... Azi, do you have any thoughts on this? What about fertigation through the tube vs. fertigation directly to the soil? Maybe some nutrients require the soil microbes in order to be absorbed?

Again, I'd make sure enough N is being given, and the supporting minerals for N... Fe, Zn, Mn. Also, make sure there's enough sulfur.

 

[Weffalo]

nice defol.

the top shots still have the plant looking underfed to me. a lights off shot to get the true color of the tops would be a good idea. i think the light could be washing it out.

@bluter I'll grab a pic with lights off, to my eyes the green has gotten deeper at the canopy, it's hard to see and it's not uniform but not all of the leaves are as bright green as they have been.

My SIP reservoiur is only 2.5L so it could simply be an issue of my plant wanting more water but the res is empty? Not much I can do about that until next run.

Yesterday I fed with:
TA Grow: 1.8ml/L
TA Micro: .8ml/L
TA Bloom: 1ml/L
CannaCalMag: 1ml/L
Seaweed: 5ml/L

My EC was 2.03 with a PH of 6.26

This shot from a week ago tells a story...

New growth at top of canopy is pale green, while lower down is dark green. Some lower leaves going yellow. I read this possibly as... transition to flower nutes took place, and then there wasn't enough nitrogen. The plant started stealing nitrogen from the lower leaves.

@Azimuth is a SIP grower... Azi, do you have any thoughts on this? What about fertigation through the tube vs. fertigation directly to the soil? Maybe some nutrients require the soil microbes in order to be absorbed?

Again, I'd make sure enough N is being given, and the supporting minerals for N... Fe, Zn, Mn. Also, make sure there's enough sulfur.

Thanks @cbdhemp808

So Azi has guided me all of my grows already, and there is no issue with feeding directly into the res, that's how it is normally done with SIPs. He does topfeed but that's due to feeding with organic inputs I believe.

As I understand it, microbes shouldn't matter too much with chelated synthetic nutrients. I'm no expert obviously but that's my understanding from what I have read thus far.

As far as the nutrients you mentioned, the Fe, Zn and Mn is found in "Micro" of the Tri-Part, @InTheShed did calculations on my nutrients so I'm sure he accounted for those things as well as the Nitrogen and Sulphur. I've been feeding the ratios he advised for 8 days now.

I'll grab some more pics now before I head out for work, not checked on her today hopefully it's more positive progress!

 

[Weffalo]

Rushing out but here's some quick pics from today, first few are with leds on, last one with dark mode and rest flash:

still a few more leaves yellowing today too, only lower growth though as yesterday:

 

[cbdhemp808]

lookin' better!

 

[Azimuth]

New growth at top of canopy is pale green, while lower down is dark green. Some lower leaves going yellow. I read this possibly as... transition to flower nutes took place, and then there wasn't enough nitrogen. The plant started stealing nitrogen from the lower leaves.

@Azimuth is a SIP grower... Azi, do you have any thoughts on this? What about fertigation through the tube vs. fertigation directly to the soil? Maybe some nutrients require the soil microbes in order to be absorbed?

Nitrogen is a mobile element so if that was the issue I would expect the top most leaves to be the darkest green and the lower most leaves yellow which is not the case here.

Maybe just too low a level of nutes? Synthetic nutes can go right down the fill pipe no problem. Organics do seem to benefit from some top dressing though I'm trying it both ways.

 

[bluter]

Nitrogen is a mobile element so if that was the issue I would expect the top most leaves to be the darkest green and the lower most leaves yellow which is not the case here.

he's feeding nitrogen heavy and his nutes are still balanced to veg / preflower.

Maybe just too low a level of nutes?

i'd be feeding them for flower by this time with more emphasis on p/k. i might not go the full flower schedule, but i'd definitely be moving toward it now.

he's about double the grow, and half the micro and bloom if you go by the nute company feed charts.

the plants do look a bit better. i think they got some of the n back in but are looking for the pk at the same time.

 

[Weffalo]

he's feeding nitrogen heavy and his nutes are still balanced to veg / preflower.







i'd be feeding them for flower by this time with more emphasis on p/k. i might not go the full flower schedule, but i'd definitely be moving toward it now.

he's about double the grow, and half the micro and bloom if you go by the nute company feed charts.

the plants do look a bit better. i think they got some of the n back in but are looking for the pk at the same time.

Thanks a lot @bluter From advice I've received I can just up K with Potassium Sulphate and I should be at the right ratios for flower? Or do they also look like they also need more P?

I'm actually only just getting round to watching and reading the links in @farside05 's journal but I believe the jist of it is how we don't need to use so much P in flower and most of it doesn't get used, do my plants show signs of P def in your opinion?

Sorry for double checking everything but I'm very keen to get it right with any adjustments, I realllllllllllly need this plant to finish strong, I'd estimate she has cost upwards of $600 to get to this point and she needs to deliver tasty meds for the next few months if possible, I'm doing nightly prayers to the cannabis gods

@InTheShed Sorry mate I know you've spent a lot of time on this already but could you confirm this for me please mate? Or is your advice still to wait another week before adjusting again? I have additional Sulphate arriving tomorow so I can adjust Tri-Part ratios but I also have the K booster available if that helps get the ratios right easier.

Should I just add in 1.3ml/L of the potassium solution and good to go? Will that not be too strong on the EC or no worries?

Thank you in advance

 

[farside05]

Thanks a lot @bluter From advice I've received I can just up K with Potassium Sulphate and I should be at the right ratios for flower? Or do they also look like they also need more P?

I'm actually only just getting round to watching and reading the links in @farside05 's journal but I believe the jist of it is how we don't need to use so much P in flower and most of it doesn't get used, do my plants show signs of P def in your opinion?

Sorry for double checking everything but I'm very keen to get it right with any adjustments, I realllllllllllly need this plant to finish strong, I'd estimate she has cost upwards of $600 to get to this point and she needs to deliver tasty meds for the next few months if possible, I'm doing nightly prayers to the cannabis gods

@InTheShed Sorry mate I know you've spent a lot of time on this already but could you confirm this for me please mate? Or is your advice still to wait another week before adjusting again? I have additional Sulphate arriving tomorow so I can adjust Tri-Part ratios but I also have the K booster available if that helps get the ratios right easier.

Should I just add in 1.3ml/L of the potassium solution and good to go? Will that not be too strong on the EC or no worries?

Thank you in advance

You can start the Potassium Sulfate as soon as it's in your hands with no detrimental effect. If you stick with Shed's calculations and just add the Potassium Sulfate, you'll have 29ppm of P which is perfectly fine. I target 30ppm for my girls at full maturity. As an experiment to see exactly how little P cannabis needs, I grew a plant for 180 days with only 18ppm of P. It never showed any P deficiency even at that low level.

PXL_20220123_152558456.jpg

• farside05
• Jan 23, 2022

 

[Weffalo]

You can start the Potassium Sulfate as soon as it's in your hands with no detrimental effect. If you stick with Shed's calculations and just add the Potassium Sulfate, you'll have 29ppm of P which is perfectly fine. I target 30ppm for my girls at full maturity. As an experiment to see exactly how little P cannabis needs, I grew a plant for 180 days with only 18ppm of P. It never showed any P deficiency even at that low level.

PXL_20220123_152558456.jpg

• farside05
• Jan 23, 2022

Thank you very much @farside05 - I'll add it to the regime as soon as it arrives.

Very interesting! Well I feel like I have a better grasp on what nutrients the plant needs in flower now so thanks a ton. I was planning to get some LoS and try an organic tent soon as there's a really good UK based supplier that's similar to BuildASoil, the problem I now have is both their grow & bloom feeds are super P heavy so I may have to look elsewhere.

I'm guessing in most cases it doesn't cause too many problems, it's just a waste of resources? I say that because the majority of nute companies have excess P and I assume lots of people use them without too many issues?

 

[farside05]

I say that because the majority of nute companies have excess P and I assume lots of people use them without too many issues?

I do a comparison of different nute companies and what their products come out to on a ppm basis OVER HERE. I see excessive P issues most commonly with Fox Farms. You can see in the link previously mentioned that they use way more P than any other product line. Is it a coincidence that they also recommend flushing several times a grow? I say no, and the reason is to rinse away all the unused P.

 

[Weffalo]

I do a comparison of different nute companies and what their products come out to on a ppm basis OVER HERE. I see excessive P issues most commonly with Fox Farms. You can see in the link previously mentioned that they use way more P than any other product line. Is it a coincidence that they also recommend flushing several times a grow? I say no, and the reason is to rinse away all the unused P.

Very interesting, that makes a lot of sense. You've clearly done a lot of work on the subject, thanks for sharing the knowledge

Judging by those ratios unfortunately it does seem the ratios are off on these organic dry amendments I was planning to try. Their grow NPK is 4-6-4 and the Bloom is 2-6-8 and I believe the soil comes pre-amended with the Grow.

I might shoot them an email about it and see if they could knock up something different. It is good to be able to deal with local companies and I am keen to try out a seperate organics tent without the hassle of making/sourcing anything myself

 

[bluter]

i agree it's really the k where the ask is. tips and slightly yellow edges. it's not very deep yet.

 

[GreenFingaz]

You can start the Potassium Sulfate as soon as it's in your hands with no detrimental effect. If you stick with Shed's calculations and just add the Potassium Sulfate, you'll have 29ppm of P which is perfectly fine. I target 30ppm for my girls at full maturity. As an experiment to see exactly how little P cannabis needs, I grew a plant for 180 days with only 18ppm of P. It never showed any P deficiency even at that low level.

PXL_20220123_152558456.jpg

• farside05
• Jan 23, 2022

Thats a stocky little beast lol

 

[InTheShed]

Sorry mate I know you've spent a lot of time on this already but could you confirm this for me please mate?

No problem. I'll get you new numbers with the potassium sulfate included.

Does your seaweed have an NPK value or is it just for good vibes?