yellowing new growth early in flower, mag defceincy?

[max_well]

yellowing new growth early in flower, mag defciency?

Hello farmers. A little help here would be appreciated..
Got some serious yellowing of new growth a week into flower. Strains Albert Walker and Chemdog #4. Things looked pretty good in veg, started yellowing soon after switch to 12-12. Albert Walker exhibiting strong interveinal chlorosis / yellowing, primarliy in new growth. Chemdog #4 showing signs of mag deficiency below, with some strange yellow splotchiness up top as well. Not sure if mag deficiency could explain the yellowing new growth issues, as all I've read suggests that this deficiency effects older growth.

Growing in coco , DTW, Canna coco and nutes at recommended levels, and 5mL/gal Calmag with every watering (EC ~1.6 now, pH always 5.8-5.9, meters calibrated). I'm in a sealed room, environment is great. Using 1000w hortilux hps.

Any insights are welcomed, thanks y'all
Max
Al Walker

Chemdog #4

 

[TrichromeFan]

max,
what meter are you using exactly?

You say Canna nutes at recommended levels, exactly what is your mix? Which schedule?

Have these girls had a flush recently?

-TF

 

[max_well]

Hey TF
thanks for your input... I followed your thread on the coco forum, saw that you had a little confusion with feed strength on the canna schedule, and underfed them. I've used Canna for long enough to know that their normal feed schedule does not need to be stepped down (as is is needed for many nutrient lines recommended dose). I've been using simple formula of Calmag at 5 ml/gal, and Canna A&B at ~8-10 ml/gal to give an EC of 1.3-1.6 (blue truncheon meter), stepped up along the way. Plants are flushed with every watering at least 10%, drain-to-waste. Maybe the yellowing ladies are hungry you're thinking? I guess I'll up the A&B to 1.8 EC on the next watering of a few and see how they do. I do notice that those directly under light are most affected, which could suggest they need more nutes. Thanks for any further thoughts? and good luck with the finish of your present run.
Max

 

[TrichromeFan]

How close are they to the light? Specifically the ones yellowing? Horizontal reflector? Air cooled?

Another factor could be even that the plants that are under the light are transpiring faster, uptaking quicker, and coco drying out faster perhaps? That could factor in higher salt buildups to a plant that needs more food since it is working harder under the brightest sun so to speak. Just possibilities. My plants were the most affected nearest the lights in my room.

-TF

 

[Seamaiden]

I'm thinking they are looking a little bit hungry. It looks like they're really chugging away putting out all kinds of new growth, might really need a decent boost of N.

 

[max_well]

TriFan and Seamaiden
Thanks for the thoughts!
My plants are not particularly close to lights, canopy temps are fine.
I've been reading though this helpful guide:
Seems thorough. The text on Mg deficiency seems to potentially match what I am seeing in the new growth... also possibly Fe deficiency, although I think that would be more anomalous using a complete nutrient like Canna. It's clear from my last photo above that Mg deficiency is at least present in the Chemdog #4, as this edge coloring matches photos I have seen online describing Mag def. very closely.
Here is a link to an article in maximum yield breaking down some of the causes of yellowing, differentiating between N, Mg, Fe deficiency warning signs:

I'm gonna add some Mg in the form of epsom to my mix on a few test subjects (maybe do a little foliar as well).. on a few others I'll up the overall feed ppm, and see who gets happy first. Thanks again for insights and suggestions
Max

 

[Seamaiden]

It's a matter of light being the driver, the engine, if you will, of the plants' growth. That's a big part of why proximity to lights (artificial) is important, too. :)

Just do the foliar to see most quickly whether or not the MgSO4 is deficient, first. Use 1/4 teaspoon per gallon of clean water, use a surfactant (something that breaks the surface tension and allows better absorption by the plant) and be sure to hit the undersides of the leaves. Wait and watch, see if they green back up or what.

 

[Snow Crash]

I'll go out on a limb and actually propose this is a cation issue. I have Cal-Mag Plus, Canna Coco A+B, clean water, and a perfectly calibrated (to 1394ppm) Hanna Gro'Chek pH/EC/PPM meter and I know exactly what a 10ml A, 10ml B, and 5ml Cal-Mag Plus comes out to.

You're looking at more like 1.95EC at that strength even in RO water.

If you haven't calibrated that meter (do you even need to calibrate the Blue Labs?) then if I were you that'd be a good starting point. Ensuring your meter is calibrated will help diagnose the problem going forward.

The nutrient ratio you are running right now is close to a 4-1-2 with an equal amount of Calcium to Nitrogen. If you've been doing this for a while, and the plant has been in this planter for a few weeks, then you've likely filled the Calcium buffer. Pushing continuously high levels of Calcium (in addition to what is already in the A+B) will cause an issue with the uptake of other elements.

I find the first few weeks of flowering to be the most difficult in coco. My approach during the stretch period is to run a much more balanced 1-1-1 (or a 2-2-3) and to watch my runoff EC very closely.

In addition, with regards to the Canna nutrient schedule, you should be running the 0-2-1 Cannazym at full strength right now to help balance out the PK ratios. This ratio fixer is a critical component of the Canna system.

My suggestion to you is this:

The next time you water feed mix up a solution of just the A+B at exactly 1.0ec. When you feed I want you to collect maybe 1-2L of runoff and test the EC. If it is over 1.3ec that means you're washing out a lot of excess. That means you need to continue rinsing your media with the 1.0ec solution until the deviance between what is going in and what is coming out is within 30% (or 1.0 in and <1.3 out)

Going forward into weeks 3 and 4 this will help ensure you have a clean media that still has its high CEC and complete Calcium buffer. After the 1.0EC "rinsing" then you can incorporate your Cannazym or other high phosphorus supplement to balance out the ratios.


But if you take anything away from this post I want it to be the diligence required of new Coco growers to runoff and testing of that runoff. It doesn't matter what strength solution you are using if the runoff is over 3.0EC. Gotta rinse, never flush, and hit week 3 of flowering ready to be pushed.

 

[max_well]

THanks Seamaiden
Sound like a plan..
In my experience it's true that higher light intensities will put higher demands on the plant, and deficiencies will show up in plants with highest growth demands first.
There are a lot of dynamics to understand about how deficiencies develop in plants as they are transitioning to flower, and it seems that there are special considerations to make note of in coco for this transition.
I've seen some suggest a drop in Ca to allow better uptake of Mg, at this stage of growth, and I know that excess K can also inhibit Mg uptake. I know these are all strain dependent tendencies, and there are too many parameters at play for definitive answers all the time.. just have to be consistent and take good notes of what works in a particular setup with particular conditions and adjustments! photo logging these responses helps me a lot.
I'll post updates as they develop!
thanks for continued suggestion!
Max

 

[max_well]

Hey SC
Thanks for your insight-- just posted before seeing your response with noted potential that Ca excess could be competing with Mg, and that might be causing a lockout issue, if the problem is in fact primarily Mg deficiency...
I agree that the transition to flower feed seems particularly important in coco.

In respect to the EC issue, the ~8-10 ml/gallon of the Canna A&B approximate, and I use EC as a guide (diluting mix to ~1.6 EC , max 1.7, at present with RO if it comes up high) . I've been in the habit of starting mix with ~0.3 EC of calmag in RO, and then adding A&B to desired final EC, and this has worked well with most strains through flower in my coco experience.

I will try the flush and test the runoff collection as you suggest on one or more plants exhibiting the deficiency, and post my results tonight.
Yes, I see that Cannazyme has a significant contribution to the nutrient balance, beyond enzymatic properties. 0-2-1 is something to note for certain, especially if incorporated at the suggested 10 ml/gal. Would using something with similar ratio be appropriate (such as Botanicare Hydroplex, which is 0-10-6, at ~ 2 ml/gallon, to meet the balanced suggested in the Canna program)? this substitution would be more cost effective, as I've heard differing thoughts about the utility / necessity of enzymes as a required component. Although I don't know that this would aid Mg uptake, as excess K can also inhibit Mg.
I appreciate your time and your post! all the best
Max

 

[Snow Crash]

You're in my head!!!

I use Botanicare Hydroplex right from the get go. At 0-10-6 you can use 20% of what you would with the Cannazym for about the same ratio balancing. With both products being about the same price I made the switch two grows ago and I love the stuff. All it takes is a ml or two during the first 4 weeks and then you can pump it up during weeks 5-7 on a 10 week strain.

I do not read this as a magnesium deficiency. The "meat" of your leaves looks not too bad. The issue appears to be located primarily around the leaf edges which at this stage could indicate a couple things.

Here's a picture of Mag deficiency in coco during flowering from my own garden. It was resolved with a foliar spray. You can see how mag impacts more of the central part of the leaf (lower large leaf) rather than the edges like you see in your own plant.

 

[treehugger]

Snow Crash, my hat's off to you Sir, excellent posts.

I had similar thoughts as yours, although not as rigorously documented. In addition i also question the calibration of his ph meter, or suspect ph creep - as the pillowing on the new growth is usually symptomatic of such circumstances.

 

[max_well]

Thanks for the input again, and SC thanks for the photo.
Yes, my issue doesn't look like textbook Mg deficiency .. put it's not the solution pH .. meter calibrated at 4.0, 7.0 every use. Also , 3 other strains in the room looking pretty perfect, and all are getting the same diet.
So I think it's a deficiency.
My issue actually looks pretty close to those in this thread:

Which was diagnosed as an Fe problem.. Seems like a more obscure kind of issue, especially in coco using a complete hydro nutrient. But could be a strain thing. Any thoughts on Fe? Calmag contains 0.1% iron from iron EDTA.
thanks
Max

 

[Snow Crash]

Thanks for the input again, and SC thanks for the photo.
Yes, my issue doesn't look like textbook Mg deficiency .. put it's not the solution pH .. meter calibrated at 4.0, 7.0 every use. Also , 3 other strains in the room looking pretty perfect, and all are getting the same diet.
So I think it's a deficiency.
My issue actually looks pretty close to those in this thread:

Which was diagnosed as an Fe problem.. Seems like a more obscure kind of issue, especially in coco using a complete hydro nutrient. But could be a strain thing. Any thoughts on Fe? Calmag contains 0.1% iron from iron EDTA.
thanks
Max

Iron deficiency appears as pale, weak, new growth. Definitely a concern with coco and canna but not something to worry about in your particular situation. The Cal-Mag Plus is providing enough Fe, you don't really need much of the stuff. If you do have an iron deficiency it is more likely a cation salinity issue than a genuine deficiency.

I don't know how you use the logic of "All the other plants are getting the same food and they look fine so this must be a deficiency." It is just as likely an element imbalance than any thing else. Based on the time the plants have been in the coco, the nutrients you are using, and my experience you need to start by looking at the runoff before making a claim either way.

All I think you really need to do is cut back on the Cal-Mag Plus, add a touch of Epsom Salt, and incorporate the Cannazym substitute at a low level. Minor changes to the ratios at this point is a good thing.

 

[Pimples]

I'll go out on a limb and actually propose this is a cation issue. I have Cal-Mag Plus, Canna Coco A+B, clean water, and a perfectly calibrated (to 1394ppm) Hanna Gro'Chek pH/EC/PPM meter and I know exactly what a 10ml A, 10ml B, and 5ml Cal-Mag Plus comes out to.

You're looking at more like 1.95EC at that strength even in RO water.

If you haven't calibrated that meter (do you even need to calibrate the Blue Labs?) then if I were you that'd be a good starting point. Ensuring your meter is calibrated will help diagnose the problem going forward.

The nutrient ratio you are running right now is close to a 4-1-2 with an equal amount of Calcium to Nitrogen. If you've been doing this for a while, and the plant has been in this planter for a few weeks, then you've likely filled the Calcium buffer. Pushing continuously high levels of Calcium (in addition to what is already in the A+B) will cause an issue with the uptake of other elements.

I find the first few threads of flowering to be the most difficult in coco. My approach during the stretch period is to run a much more balanced 1-1-1 (or a 2-2-3) and to watch my runoff EC very closely.

In addition, with regards to the Canna nutrient schedule, you should be running the 0-2-1 Cannazym at full strength right now to help balance out the PK ratios. This ratio fixer is a critical component of the Canna system.

My suggestion to you is this:

The next time you water feed mix up a solution of just the A+B at exactly 1.0ec. When you feed I want you to collect maybe 1-2L of runoff and test the EC. If it is over 1.3ec that means you're washing out a lot of excess. That means you need to continue rinsing your media with the 1.0ec solution until the deviance between what is going in and what is coming out is within 30% (or 1.0 in and <1.3 out)

Going forward into weeks 3 and 4 this will help ensure you have a clean media that still has its high CEC and complete Calcium buffer. After the 1.0EC "rinsing" then you can incorporate your Cannazym or other high phosphorus supplement to balance out the ratios.


But if you take anything away from this post I want it to be the diligence required of new Coco growers to runoff and testing of that runoff. It doesn't matter what strength solution you are using if the runoff is over 3.0EC. Gotta rinse, never flush, and hit week 3 of flowering ready to be pushed.

Old thread but SC is very spot on with this post. Damn. I know plants and hydroponic mineral nutrition like the back of my hand and this post is very well worded.

 

[Samoan]

I'll go out on a limb and actually propose this is a cation issue. I have Cal-Mag Plus, Canna Coco A+B, clean water, and a perfectly calibrated (to 1394ppm) Hanna Gro'Chek pH/EC/PPM meter and I know exactly what a 10ml A, 10ml B, and 5ml Cal-Mag Plus comes out to.

You're looking at more like 1.95EC at that strength even in RO water.

If you haven't calibrated that meter (do you even need to calibrate the Blue Labs?) then if I were you that'd be a good starting point. Ensuring your meter is calibrated will help diagnose the problem going forward.

The nutrient ratio you are running right now is close to a 4-1-2 with an equal amount of Calcium to Nitrogen. If you've been doing this for a while, and the plant has been in this planter for a few weeks, then you've likely filled the Calcium buffer. Pushing continuously high levels of Calcium (in addition to what is already in the A+B) will cause an issue with the uptake of other elements.

I find the first few weeks of flowering to be the most difficult in coco. My approach during the stretch period is to run a much more balanced 1-1-1 (or a 2-2-3) and to watch my runoff EC very closely.

In addition, with regards to the Canna nutrient schedule, you should be running the 0-2-1 Cannazym at full strength right now to help balance out the PK ratios. This ratio fixer is a critical component of the Canna system.

My suggestion to you is this:

The next time you water feed mix up a solution of just the A+B at exactly 1.0ec. When you feed I want you to collect maybe 1-2L of runoff and test the EC. If it is over 1.3ec that means you're washing out a lot of excess. That means you need to continue rinsing your media with the 1.0ec solution until the deviance between what is going in and what is coming out is within 30% (or 1.0 in and <1.3 out)

Going forward into weeks 3 and 4 this will help ensure you have a clean media that still has its high CEC and complete Calcium buffer. After the 1.0EC "rinsing" then you can incorporate your Cannazym or other high phosphorus supplement to balance out the ratios.


But if you take anything away from this post I want it to be the diligence required of new Coco growers to runoff and testing of that runoff. It doesn't matter what strength solution you are using if the runoff is over 3.0EC. Gotta rinse, never flush, and hit week 3 of flowering ready to be pushed.

Aloha, was hoping to revamp this thread as I'm having similar problems and really need some guidance. I will water and check runoff as mentioned, I have only been using canna a & b with my tap. Tap is 7.7. 166ppm then I go light feeding around 400ppm and ph with citric acid crystal to around 5.8. Water about 1/4 containers once a day.
If anyone an help with this much appreciative. Mahalo

 

[Samoan]

premature orange hairs blistery stunted, pretty much no bud growth

 

[One drop]

premature orange hairs blistery stunted, pretty much no bud growth

thats not a happy looking plant 0.O.

 

[GanjaNGains]

yellowing new growth early in flower, mag defciency?

Hello farmers. A little help here would be appreciated..
Got some serious yellowing of new growth a week into flower. Strains Albert Walker and Chemdog #4. Things looked pretty good in veg, started yellowing soon after switch to 12-12. Albert Walker exhibiting strong interveinal chlorosis / yellowing, primarliy in new growth. Chemdog #4 showing signs of mag deficiency below, with some strange yellow splotchiness up top as well. Not sure if mag deficiency could explain the yellowing new growth issues, as all I've read suggests that this deficiency effects older growth.

Growing in coco , DTW, Canna coco and nutes at recommended levels, and 5mL/gal Calmag with every watering (EC ~1.6 now, pH always 5.8-5.9, meters calibrated). I'm in a sealed room, environment is great. Using 1000w hortilux hps.

Any insights are welcomed, thanks y'all
Max
Al Walker

Chemdog #4

Some defieciency going on pics would help plants switched to flower need more/stronger dose week in means still plenty of time to fix a bountiful harvest in your future