What deficiency is this?

[lilnug420]

Fem plant

10 Gal pot
Terra canna pro soil
Mega crop fertilizer
Ph adjusted to around 6
About a month away from harvest


I Always get these weird deficiencies in flower, where as in veg they're all nice and green, doesn't seem to affect yield and quality, but im wondering what it is.


Upping the dose of MC hasn't worked in the past so this year I'm sticking to MC calculator reccomentations

 

[SmokingWings]

I Always get these weird deficiencies in flower, where as in veg they're all nice and green, doesn't seem to affect yield and quality, but im wondering what it is.

Very possible that your plants are in a Potassium deficiency stage. The all yellow leaves that I noticed are often a sign of Nitrogen or Potassium shortage and sometimes a shortage of both nutrients.

A Potassium shortage often shows as a yellowing of the tip and then the tips along the serrated edges of the fingers on the leaf. Eventually the edges turn yellow followed by a browning.

Often, as you have noticed, the plants are doing great while in the vegetating stage and then 2 or 3 weeks after flowering starts the problem signs start to show. My belief is that that the plant starts to demand more Nitrogen and Potassium than is available from the soil. Sometimes the grower cuts back on the fertilizers out of concern that the plant will be over fertilized. No matter, the problem starts and once started it can quickly become serious looking. Thing is that increasing the Potassium once the problem shows often does not stop it. But, the added Potassium and often a bit more Nitrogen can slow down the damage which is a win.

I have noticed that if I increase the levels of "flowering" fertilizers starting about 2-3 weeks before flowering starts often delays the signs of deficiency to the last couple of weeks. And, the signs are not as severe as they used to be.

I do not use Mega Crop so can't help with that. There is a Mega Crop thread here so maybe someone has discussed tweaks to the schedule that you might find helpful. It is a couple of years old and kinda long but maybe it will help.

https://www.420magazine.com/community/threads/the-mega-crop-thread.471944/

 

[lilnug420]

Very possible that your plants are in a Potassium deficiency stage. The all yellow leaves that I noticed are often a sign of Nitrogen or Potassium shortage and sometimes a shortage of both nutrients.

A Potassium shortage often shows as a yellowing of the tip and then the tips along the serrated edges of the fingers on the leaf. Eventually the edges turn yellow followed by a browning.

Often, as you have noticed, the plants are doing great while in the vegetating stage and then 2 or 3 weeks after flowering starts the problem signs start to show. My belief is that that the plant starts to demand more Nitrogen and Potassium than is available from the soil. Sometimes the grower cuts back on the fertilizers out of concern that the plant will be over fertilized. No matter, the problem starts and once started it can quickly become serious looking. Thing is that increasing the Potassium once the problem shows often does not stop it. But, the added Potassium and often a bit more Nitrogen can slow down the damage which is a win.

I have noticed that if I increase the levels of "flowering" fertilizers starting about 2-3 weeks before flowering starts often delays the signs of deficiency to the last couple of weeks. And, the signs are not as severe as they used to be.

I do not use Mega Crop so can't help with that. There is a Mega Crop thread here so maybe someone has discussed tweaks to the schedule that you might find helpful. It is a couple of years old and kinda long but maybe it will help.

https://www.420magazine.com/community/threads/the-mega-crop-thread.471944/

Last year i did try to up the fertilizer and it didn't help, im worried i will overfertilize, is it possible that it's a lockout or burn?


I can try upping the nutes, but mc is already very high in nitrogen so im Surprised it's a N deficiency

 

[SmokingWings]

I can try upping the nutes, but mc is already very high in nitrogen so im Surprised it's a N deficiency

It is not necessarily a Nitrogen deficiency because the signs of low Potassium can be similar. Look at both nutrients and try changes in each to see what happens. The plants need more Nitrogen in flower than many realize. It is necessary to the development of all the green plant material that the plant is growing when it grows the flowers.

I give my plants a Nitrogen boost when flowering by adding a liquid fish product to the watering every 10 to 14 days.

A dose of Potassium is easy to do by using a liquid product made with Kelp seaweed. Or top-dressing with finely ground up Kelp Meal product. The Potassium is important to overall plant health and I will add this to the schedule with a 10 to 14 day watering.

 

[Bill284]

It is not necessarily a Nitrogen deficiency because the signs of low Potassium can be similar. Look at both nutrients and try changes in each to see what happens. The plants need more Nitrogen in flower than many realize. It is necessary to the development of all the green plant material that the plant is growing when it grows the flowers.

I give my plants a Nitrogen boost when flowering by adding a liquid fish product to the watering every 10 to 14 days.

A dose of Potassium is easy to do by using a liquid product made with Kelp seaweed. Or top-dressing with finely ground up Kelp Meal product. The Potassium is important to overall plant health and I will add this to the schedule with a 10 to 14 day watering.

Good morning Amigo.
This is basically my first run with MC in the greenhouse & VIVOHUT.
I have found it very high in nitrogen.
If I up the dose in flower I get the deep deep green leaves with the curl.
I dropped back to 1 gram per litre and give a little extra p&k and the girls are very happy.
I love the MC through to about mid flower after that I find it lacking.
Just an observation I've made.
Take care.
Edit BTW. that's coco and I feed every day.

B43E1EAE-22F7-4EB3-A507-29BFF0CAF862.jpeg

• Bill284
• Oct 3, 2023
• #@bill284 method

Miami Miami 10/2/23
@NorthAtlanticSeedCo.
Mc

#VIVOSUN #Love What You Grow
Bill284

 

[Melville Hobbes]

What size are your pots and how long have the plants been in them?

 

[lilnug420]

It is not necessarily a Nitrogen deficiency because the signs of low Potassium can be similar. Look at both nutrients and try changes in each to see what happens. The plants need more Nitrogen in flower than many realize. It is necessary to the development of all the green plant material that the plant is growing when it grows the flowers.

I give my plants a Nitrogen boost when flowering by adding a liquid fish product to the watering every 10 to 14 days.

A dose of Potassium is easy to do by using a liquid product made with Kelp seaweed. Or top-dressing with finely ground up Kelp Meal product. The Potassium is important to overall plant health and I will add this to the schedule with a 10 to 14 day watering.

Im only running MC, should i try to just up the dose?

So just to confirm this is definitely not lockout or burn?

 

[lilnug420]

Any thoughts @Emilya Green ?

 

[Melville Hobbes]

Ok, 10 gallon pot, but how long has she been in it?
The reason I ask is I had problems in flower when using MC for my outdoor plants last year.
It looked like a potassium deficiency, but bumping the MC didn’t help.
I had them in 7 gallon fabric pots, but for a really long time, and it was suggested they were rootbound.
It looks like you're in plastic pots in the pic, so you would get rootbound faster.

 

[lilnug420]

Ok, 10 gallon pot, but how long has she been in it?
The reason I ask is I had problems in flower when using MC for my outdoor plants last year.
It looked like a potassium deficiency, but bumping the MC didn’t help.
I had them in 7 gallon fabric pots, but for a really long time, and it was suggested they were rootbound.
It looks like you're in plastic pots in the pic, so you would get rootbound faster.

Its fabric pot, definitely not rootbound, i couldn't even fill out a 7gal pot last year

 

[lilnug420]

Good morning Amigo.
This is basically my first run with MC in the greenhouse & VIVOHUT.
I have found it very high in nitrogen.
If I up the dose in flower I get the deep deep green leaves with the curl.
I dropped back to 1 gram per litre and give a little extra p&k and the girls are very happy.
I love the MC through to about mid flower after that I find it lacking.
Just an observation I've made.
Take care.
Edit BTW. that's coco and I feed every day.

B43E1EAE-22F7-4EB3-A507-29BFF0CAF862.jpeg

• Bill284
• Oct 3, 2023
• #@bill284 method

Miami Miami 10/2/23
@NorthAtlanticSeedCo.
Mc

#VIVOSUN #Love What You Grow
Bill284

Im not getting green curly leaves so should i up the dose? Currently at 6.5g/5L

 

[lilnug420]

Im getting a bit confused here guys, can anyone confirm this is not a lockout or a toxicity?

As far as i know they can look very similar?


And as far what to do, should i up the MC dosage?

 

[Melville Hobbes]

You can try that, but if it's a lockout it won't help.
How long do you go between waterings?

 

[lilnug420]

You can try that, but if it's a lockout it won't help.
How long do you go between waterings?

3-4 days now

Is there anyway to know for sure?

I water 6.5g/5l if mega crop, a bit lower than MC recommends as other years i tried more and still got these weird issues in flower, where as in veg they were Always very healthy green

 

[Melville Hobbes]

Then I would try raising the MC. It doesn't look like a toxicity to me, and the level you're feeding at is a little less than I'm giving my outdoor plant right now.
On the other hand I'm supplementing it with some magnesium nitrate on the advice of @InTheShed .

 

[lilnug420]

Then I would try raising the MC. It doesn't look like a toxicity to me, and the level you're feeding at is a little less than I'm giving my outdoor plant right now.
On the other hand I'm supplementing it with some magnesium nitrate on the advice of @InTheShed .

By how much should i up?

Also, im about a month away from harvest more or less

 

[Melville Hobbes]

Missed the edit.
A lot of us were getting issues with yellowing leaves in flower with MC. Shed and some others felt the calcium and potassium were too high leading to imbalances at higher dosages in the latter half of flower.
The magnesium nitrate I'm using helps. As I understand it, raising the ratio of mag to cal, and of N to K brings it back into balance.
My outdoor plant is at 6g/gallon MC, with 1g of mag nitrate.
You can try raising it to 6 or 7g per gallon, or you could go the other way. I know a grower who doesn't go above 4.5g per gallon the entire grow and doesn't get the same issues.
Sorry I'm not much help right now, I'm trying to deal with a situation here, and it's taking up most of my attention.
The last time I had this issue with MC before the mag nitrate I wasn't able to stop it, but the plant got through to harvest, just with a lot of yellowed leaves.
If you're really worried about a lockout the only way to resolve that would be a flush to reset the medium followed by resuming feeding.

 

[Bill284]

Just out of curiosity.
My apologies if you said this already.
In soil I feel dry a little water dry a bit feed a little dry water etc.
Is this how your feeding.
I'm using 1 gm per litre of mc and .5 ml per liter of Remo flower.
Girls love it.
Also calmag every feed and a little B1.




#VIVOSUN #Love What You Grow
Bill284

 

[Regrowth]

1.3/L seems low but I mostly grow clones and find them to be a little more hungry than usual, even during veg.
I pretty much feed 1.5/L from start to finish and looking at the MC chart I think that's around where you should be.
I don't really bother going any higher. I rarely add any calmag now as I think I've locked out magnesium because of it. K def seems unusual tbh. Honestly, doesn't help that GL keeps changing their formula.

 

[lilnug420]

Missed the edit.
A lot of us were getting issues with yellowing leaves in flower with MC. Shed and some others felt the calcium and potassium were too high leading to imbalances at higher dosages in the latter half of flower.
The magnesium nitrate I'm using helps. As I understand it, raising the ratio of mag to cal, and of N to K brings it back into balance.
My outdoor plant is at 6g/gallon MC, with 1g of mag nitrate.
You can try raising it to 6 or 7g per gallon, or you could go the other way. I know a grower who doesn't go above 4.5g per gallon the entire grow and doesn't get the same issues.
Sorry I'm not much help right now, I'm trying to deal with a situation here, and it's taking up most of my attention.
The last time I had this issue with MC before the mag nitrate I wasn't able to stop it, but the plant got through to harvest, just with a lot of yellowed leaves.
If you're really worried about a lockout the only way to resolve that would be a flush to reset the medium followed by resuming feeding.

Im already at around 6g/gal a gal is 3.7 liters ish no? So im pretty close to that at 6.5g/5L

Thing is, the plant next to the one with the issue in the picture, doesn't quite have so much yellowing, i will attach pics, i always have had this issue with MC, i always get to harvest with very nice smoke, but perhaps avoiding all that yellowing would give me even greater smoke.


I did a flush last night, and after watered with a little more than 13g/10L


still unsure what to do next