Potential Mag deficiency?

JHake

Well-Known Member
Environmental settings would be my main factor of concern, both light proximity and heat. And main cause of your problems. If you are under 30-32ºC, fixing that is much more important than buying "better" nutrients.

This is somewhat similar to what my previous plant looked like at the start of flowering phase (got only 1.5g from this lol, at least it was very good smelling and tasting xD). Mind that i was also probably overwatering, as well as not giving enough ferts and having higher temps with lower RH %.
Again, environment.

-----

Is there a label or detail of your soil mix? Specially the "Green composted soil conditioner (Organic composted amendments)".
Do you have more soil of that bag to top dress with?

You see somehow lost with being consistent with a method of grow. Also happened to me, information is very diffuse at first.
You started with an organic soil and have organic nutes, but chase pH like you would in hydro. Not that you can't, but...did you also adjusted pH when growing those other "fruiting plants" that did good with the same soil mix and nutes your are using for cannabis? Guess not, right? So maybe answers are outside the pH adjusting thing; and you clearly said you've been working it around 6-7.
(I want to make clear i am not against adjusting or measuring pH doing organics, but problem isn't there if you've been using 6-7).
But if you want to go organics, having a good source of EWC/compost is a must.

In my opinion, i also believe defoliation was unnecessarily severe. You could have removed less material.

Those are my general ideas about what's happening here, but being in your situation i would:

- Better environment. If not possible this grow, take it into as a big priority for the next one. Watering frequency is related also to this. I mean, water more frequently if needed, it' perfectly fine to water every day, even if lot of "guides" say that it's not.
- Top dress with the organic mix you had from beginning. If it has enough energy/nutrients, it should work, not instantly, but you will have them available in the following weeks and will help at least a little.
- Bump the dose and/or frequency of your organic bottle nutes. Not all organic bottle nute are made the same, but as general rule, it's organic matter that must be worked by the soil. Most bottles organic nutes, are somewhat already processed, so it takes less time than a solid fertilizer. I would start by keeping the same dosage you've been using, but more frequently, like 2x a week.
- Do a foliar feeding, either with the nutrients you already had, or try the foliar epsom salts if you believe it's Mg related.
 

curious2garden

Well-Known Mod
Staff member
Environmental settings would be my main factor of concern, both light proximity and heat. And main cause of your problems. If you are under 30-32ºC, fixing that is much more important than buying "better" nutrients.



Again, environment.
.......snip.....
I grow indoors in the Mojave Desert. I do not air condition my house. My plants are fine and their canopy remains at 95-105 (35-41) from July to September/October. My humidity runs roughly 10%. Unless both your humidity and temps are very high I would not worry too much about environment at this point. Instead I'd be looking at soil mix, nutrients and light.
 
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curious2garden

Well-Known Mod
Staff member
...snip...
Mind that i was also probably overwatering, as well as not giving enough ferts and having higher temps with lower RH %.
...snip...
I run high temps and low humidity. It's ok, you can't run high temp and high humidity or you close the leave's stoma.
 

Entusia

Well-Known Member
Not familiar with your soil but most of us dont pH our water when using these organic soils.
This soil works well in your garden you mentioned.Do you feed them the same way?
You mentioned runoff feeds.
I don't feed the same way: i just got a few ornamentals, one acidophilic and a pepper plant. I only feed when they look "tired" and have less flowers/fruits than normal. After 3 days max they're all usually in tip-top shape. I water every other day (or every day if it's very hot outside) and don't even look if there's some run-off or not, but usually there isn't any.

Runoff feeds indoors were advised to me by someone in my previous post (link). I trusted this advice since it was very straightforward and well motivated, but now that the newest Biobizz feeding schedule sheet arrived with the Biobizz Starters Pack, it mentions clearly:
"Water 2-3 times a week, no need to water till run-off."

So yeah, that was a mishap.
I don't have much experience so i follow what more experienced people say, especially if they give reasons and rationalize concepts.
Now that i know what the manufacturers recommends i think i'll stick with that.

Today i watered again with 6.7-6.8 pH water and again fed with the same doses of Biogrow, Biobloom and Topmax to try and exclude Cause 0) incorrect pH and Cause 1) not enough nutrients from the list of candidates to pinpoint exactly the cause of this leaf discoloration.

Next week or earlier i'll try adding Bioheaven, Calmag and RhinoSkin to see if they're good for the plant.
 

JHake

Well-Known Member
I grow indoors in the Mojave Desert. I do not air condition my house. My plants are fine and their canopy remains at 95-105 (35-41) from July to September/October. My humidity runs roughly 10%. Unless both your humidity and temps are very high I'd would not worry too much about environment at this point. Instead I'd be looking at soil mix, nutrients and light.
Most of the times i ended up growing better weed was because of being able to have better environment, but it's true that environment it's not a single factor (like temps), but the sum of all of them and their correlations. As you said, those same high temps could be worse depending also on RH.
Anyway is very cool to know that an experienced user like you can manage those temps. I mean, next time i'm facing something like 30ºC won't get so mad about it then and know i can work around it.
 

Entusia

Well-Known Member
I don't feed the same way: i just got a few ornamentals, one acidophilic and a pepper plant. I only feed when they look "tired" and have less flowers/fruits than normal. After 3 days max they're all usually in tip-top shape. I water every other day (or every day if it's very hot outside) and don't even look if there's some run-off or not, but usually there isn't any.

Runoff feeds indoors were advised to me by someone in my previous post (link). I trusted this advice since it was very straightforward and well motivated, but now that the newest Biobizz feeding schedule sheet arrived with the Biobizz Starters Pack, it mentions clearly:
"Water 2-3 times a week, no need to water till run-off."

So yeah, that was a mishap.
I don't have much experience so i follow what more experienced people say, especially if they give reasons and rationalize concepts.
Now that i know what the manufacturers recommends i think i'll stick with that.

Today i watered again with 6.7-6.8 pH water and again fed with the same doses of Biogrow, Biobloom and Topmax to try and exclude Cause 0) incorrect pH and Cause 1) not enough nutrients from the list of candidates to pinpoint exactly the cause of this leaf discoloration.

Next week or earlier i'll try adding Bioheaven, Calmag and RhinoSkin to see if they're good for the plant.
Please mind that when i mention 6.7-6.8 pH i'm testing with GH liquid pH test kit, 2 drops, and both this and the last watering/feeding the pH value was reached without using any pH down (I'm also using the Biobizz organic pH down called "Bio Down"). So no pH adjustment: pure tap water (dechlorinated by 48h evaporation) + nutes.
 

curious2garden

Well-Known Mod
Staff member
Most of the times i ended up growing better weed was because of being able to have better environment, but it's true that environment it's not a single factor (like temps), but the sum of all of them and their correlations. As you said, those same high temps could be worse depending also on RH.
Anyway is very cool to know that an experienced user like you can manage those temps. I mean, next time i'm facing something like 30ºC won't get so mad about it then and know i can work around it.
Mine seem to muddle through somehow.
muddlethrough - 1.jpeg
 

myke

Well-Known Member
I don't feed the same way: i just got a few ornamentals, one acidophilic and a pepper plant. I only feed when they look "tired" and have less flowers/fruits than normal. After 3 days max they're all usually in tip-top shape. I water every other day (or every day if it's very hot outside) and don't even look if there's some run-off or not, but usually there isn't any.

Runoff feeds indoors were advised to me by someone in my previous post (link). I trusted this advice since it was very straightforward and well motivated, but now that the newest Biobizz feeding schedule sheet arrived with the Biobizz Starters Pack, it mentions clearly:
"Water 2-3 times a week, no need to water till run-off."

So yeah, that was a mishap.
I don't have much experience so i follow what more experienced people say, especially if they give reasons and rationalize concepts.
Now that i know what the manufacturers recommends i think i'll stick with that.

Today i watered again with 6.7-6.8 pH water and again fed with the same doses of Biogrow, Biobloom and Topmax to try and exclude Cause 0) incorrect pH and Cause 1) not enough nutrients from the list of candidates to pinpoint exactly the cause of this leaf discoloration.

Next week or earlier i'll try adding Bioheaven, Calmag and RhinoSkin to see if they're good for the plant.
I wouldn't add any other stuff,just add more of what you have already.You have epsom for mg you dont have a ca deficiency so why bother paying for calmag?
 

Entusia

Well-Known Member
Environmental settings would be my main factor of concern, both light proximity and heat. And main cause of your problems. If you are under 30-32ºC, fixing that is much more important than buying "better" nutrients.



Again, environment.

-----

Is there a label or detail of your soil mix? Specially the "Green composted soil conditioner (Organic composted amendments)".
Do you have more soil of that bag to top dress with?

You see somehow lost with being consistent with a method of grow. Also happened to me, information is very diffuse at first.
You started with an organic soil and have organic nutes, but chase pH like you would in hydro. Not that you can't, but...did you also adjusted pH when growing those other "fruiting plants" that did good with the same soil mix and nutes your are using for cannabis? Guess not, right? So maybe answers are outside the pH adjusting thing; and you clearly said you've been working it around 6-7.
(I want to make clear i am not against adjusting or measuring pH doing organics, but problem isn't there if you've been using 6-7).
But if you want to go organics, having a good source of EWC/compost is a must.

In my opinion, i also believe defoliation was unnecessarily severe. You could have removed less material.

Those are my general ideas about what's happening here, but being in your situation i would:

- Better environment. If not possible this grow, take it into as a big priority for the next one. Watering frequency is related also to this. I mean, water more frequently if needed, it' perfectly fine to water every day, even if lot of "guides" say that it's not.
- Top dress with the organic mix you had from beginning. If it has enough energy/nutrients, it should work, not instantly, but you will have them available in the following weeks and will help at least a little.
- Bump the dose and/or frequency of your organic bottle nutes. Not all organic bottle nute are made the same, but as general rule, it's organic matter that must be worked by the soil. Most bottles organic nutes, are somewhat already processed, so it takes less time than a solid fertilizer. I would start by keeping the same dosage you've been using, but more frequently, like 2x a week.
- Do a foliar feeding, either with the nutrients you already had, or try the foliar epsom salts if you believe it's Mg related.
These are all invaluable advices.
Thanks thanks thanks @curious2garden for helping me here too, i remember you from my first post ;)

Soil
This is the soil label (in Italian), it doesn't say much more than what i already wrote in earlier comments. Just some additional data:
tercomposti.jpg

What is top dress? Yes, i still have a little bit of soil left in this bag.

Defoliation
I'm using the "Controversial defoliation technique" from growweedeasy.com's k33ftr33z (link and IC Mag post) and it worked well so far.

Environment
My environment now is:
T = 24°C min (light off, 4AM) - 33 °C max (light on, 3PM)
RH = 32% min (light on, 5PM) - 59% max (light off, 5AM)

For better environment than this, i need a proper tent with plenty of grow volume and ad-hoc (noisy) equipment setup in my basement (much cooler than my bedroom) instead of:
- 35x70x70 Eket cabinet from IKEA
- Spider Farmer SF-1000 LED grow light
- Noctua NF-A14 industrialPPC-3000 PWM heavy duty industrial PC extraction fan (which honestly does its job damn good considering the inline 360/480 m³/h carbon filter mounted on it... it's running constantly at only 60% power)
- additional USB and PC fans
- DIY humidifer (i run it only during germination and early veg to reach 70% and 60% RH respectively, after it's all soil and plant transpiration)

Better equipment and basement renovation are coming and i already started working on them, not in time to help this round though!

Nutes
Bumped the frequency of feeding (keeping same doses as the recommended for Lightmix soil in the feeding schedule posted down below) to every watering (3-4 times a week) instead of only one time a week, to exclude Cause 1) not enough nutrients

BioBizz-Feeding-Schedule.jpg

Foliar feeding
Can i really spray the Biobizz nutrients? All of them? At what dosage?
Sorry, i have no idea really, but i can also try to ask the manufacturer via Email :(

All the nutrients i have now:
Rootjuice, Biogrow, Biobloom, Topmax, Bioheaven, Calmag, Rhinoskin
 

Entusia

Well-Known Member
I wouldn't add any other stuff,just add more of what you have already.You have epsom for mg you dont have a ca deficiency so why bother paying for calmag?
You're well within reason myke, thanks for always keeping me real.

I honestly bought it just in case since i was ordering other things from the same seller and i didn't have a solution for apparent Mg deficiency, but you're right, i shouldn't have.

Unfortunately i still don't have any Epsom, but i'm still looking for it!
 

JHake

Well-Known Member
Top dressing is adding something on the top layer of soil in your pot.
Common practice when doing organics is do top dressings with amendments/fertilizers and cover them in compost or EWC.
Then the microbes and other living organisms from your soil, take care of those ferts and processes them for the plant.

I checked the BioBizz website and foliar application is indicated in some of the products, but not the ones you have.
 

Entusia

Well-Known Member
Your feeding every time now?
Yes, i'm feeding every time (max 3 times a week) as recommended in the feeding schedule.
Since i water almost 4 times a week now, to make sure i'm not underwatering, i guess one watering i can just give straight pH'd water.
 

myke

Well-Known Member
Yes, i'm feeding every time (max 3 times a week) as recommended in the feeding schedule.
Since i water almost 4 times a week now, to make sure i'm not underwatering, i guess one watering i can just give straight pH'd water.
Well the green should start to come back shortly.
 

curious2garden

Well-Known Mod
Staff member
Too early to tell if it's working.
I'm fixing some images of concerning spots so we can see it better:
You don't have an Mg def that last picture shows an N def. Mg is interveinal chlorosis, you have veinal chlorosis which will progress to interveinal as well that's an N deficiency. Plus your plants are overall a little light colored. If you top dressed you'll probably be fine. I would also clean up everything below the net, nice looking plants.
 

Entusia

Well-Known Member
You don't have an Mg def that last picture shows an N def. Mg is interveinal chlorosis, you have veinal chlorosis which will progress to interveinal as well that's an N deficiency. Plus your plants are overall a little light colored. If you top dressed you'll probably be fine. I would also clean up everything below the net, nice looking plants.
I'm starting to think every error leading to this done in the last few weeks has created an intertwined set of problems/deficiencies.
I always thought early N deficiency would show interveinal chlorosis, instead of veinal chlorosis, like what is depicted here:

nitrogen-info-marijuana.jpg

But i also read that genetics (this plant comes from a bagseed) can play a part.

To me it seems like multiple problems/deficiencies stacked on top of the other in an overlay of effects, possibly caused by different errors.
One could've expedited another one, like a feedback loop of sorts. A cascading effect, if you wish.

1) N deficiency, definitely from underfeeding + 20% runoff flushing + leafy girl + fast growth

Then, could also be:
2) Fe (and Zn?) deficiencies, if the pH of the soil drifted too high.
or
3) P, K, S, Ca, Mg deficiencies, if the pH of the soil drifted too low. (not necessarily all, of course)

All this could have made the plant a little less resistant than before to the somewhat harsh growing conditions (high temp, near to the light), so it was easier for light/heat to "damage" the uppermost buds.

A side by side comparison (thanks to the webcam inside the cabinet) shows that in the last 2 to 3 days the discoloration basically stopped on the leaves that were otherwise fine, and progressed (because of N deficiency i think) on the older leaves you can see behind that are still yellowing/browning and will probably fall off soon.

4-08-vs-7-08.jpg
 

JHake

Well-Known Member
Defoliation
I'm using the "Controversial defoliation technique" from growweedeasy.com's k33ftr33z (link and IC Mag post) and it worked well so far.
How can you know it worked well?
Not bashing or anything. But if it's your first grow, you don't have a previous experience to compare. And even in that case, a previous experience isn't that much, because i'm sure you next grow will be better in more than a few aspects so lot of changes between first and second grow.

IMO, most of the time that plants do well, is because good botanical practices, not because some miracle technique or product.

I know the extreme defoliation thing is a ongoing debate with lots of good gardeners doing it, but as beginner, leaving some leaves can also teach you a few things.
Most of the will fall by themselves when needed, and they also have stored some of the nutrients you are lacking now.
You will also see that some of those lower leaves seem weak, but won't come off when you pull them. And maybe a few days or weeks later, they just fall.

It's not that i do not defoliate at all. I do remove leaves that interfere with airflow, for instance. I remove leaves that get very close together and make humidity spots. I also remove those that bother me while watering or taking a good look at the plant, even if they could have stayed.

I believe it's a good practice to go with the simpler things first. I mean...we know that leaves are important. Removing them because of something is more a supposition than anything, like: "I suppose that since cannabis is wind pollinated, i will remove leaves in order to expose the bud to air so it can fatten looking for pollen".
At first go with the fact, not the supposition, that leaves catch light and make food for the plant.
 
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Entusia

Well-Known Member
How can you know it worked well?
Not bashing or anything. But if it's your first grow, you don't have a previous experience to compare. And even in that case, a previous experience isn't that much, because i'm sure you next grow will be better in more than a few aspects so lot of changes between first and second grow.

IMO, most of the time that plants do well, is because good botanical practices, not because some miracle technique or product.

I know the extreme defoliation thing is a ongoing debate with lots of good gardeners doing it, but as beginner, leaving some leaves can also teach you a few things.
Most of the will fall by themselves when needed, and they also have stored some of the nutrients you are lacking now.
You will also see that some of those lower leaves seem weak, but won't come off when you pull them. And maybe a few days or weeks later, they just fall.

It's not that i do not defoliate at all. I do remove leaves that interfere with airflow, for instance. I remove leaves that get very close together and make humidity spots. I also remove those that bother me while watering or taking a good look at the plant, even if they could have stayed.

I believe it's a good practice to go with the simpler things first. I mean...we know that leaves are important. Removing them because of something is more a supposition than anything, like: "I suppose that since cannabis is wind pollinated, i will remove leaves in order to expose the bud to air so it can fatten looking for pollen".
At first go with the fact, not the supposition, that leaves catch light and make food for the plant.
I must be honest and clear: i didn't follow it to the letter.
It was more of a framework to work with, a "general approach" at managing growth that honestly makes sense, botanically speaking.

Also i didn't perceive any "bashing", you're just trying to help me sort things out: i can feel you're a good human being even from behind a screen ;)

I basically did what you said:
- removed leaves interfering with airflow (check)
- removed leaves stacking on top of each other (check, i had a bunch in the middle of the plant all tucked onto the other that were just degrading from lack of light and becoming mold-friendly spots)

and a little bit more:
- removed leaves shading inner or "secondary" branches and budsites (LST and scrog were conducted also to help decrease the number of "shading leaves" as much as possible)

The aim overall was to:
- have good airflow (mold, yield) -> success
- have all budsites, even lower ones, under lighting (yield) -> success, lower budsites are coming up pretty good
- contain the stretch as much as possible (avoid light problems) -> success, but i can't say if it's because of the defoliation or because of my mistakes :D

I've done "my homework" and read more than a few grow diaries in the couple of years leading to all of this (thanks, Quarantine).

And it is true, first hand experience is the most important and valuable type of experience: trying and experimenting what other people are doing and adapting different ideas to my botanical practices is a big part of the entertainment of growing for me, and also a key to get as much first hand experience as possible. Anything people do or advise, if it makes any sense i want to try. If it works for me, i keep doing it, if it doesn't i don't. I have an engineering background, so i know it's important to pinpoint any symptoms or effects, possible causes and try to understand how they relate.

Fail fast, fail hard and learn things faster. This is how i live, work, etc
At some point i'm sure my plants will yield something worthwhile, in the meantime i'll just have some fun :P

"At first go with the fact, not the supposition"
This just isn't me, I'm the exact opposite. But i appreciate your input, i really, really do. We're just different, but I will carry your words with me going forwards.
 
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