Leaf problems

[6thsense]

My plants are having some issues . This is my 5th grow and now that I think of it every one has gone this way. Ive been trying to determine the problem myself but I need more experienced eyes to help.

Some info :
Soil- ffof
Nutes - mega crop and sweet candy last feeding was 6gr mc and 2gr sc /gal
5 weeks since 12/12 flip
Well water ph’d to 6.3-6.6
Ive also have been supplementing with cal mag last feeding 6ml /gal as I thought it might be a cal def but now im not sure . Any help is appreciated thanks

 

[Sueet]

Looks like potassium deficiency.

 

[6thsense]

Looks like potassium deficiency.

Maybe . Ill add a little bud explosion next feeding and ph a little higher and see where Im at . Thx

 

[Emilya Green]

I am thinking it to be a calcium deficiency, and one that looks like it is being managed. It looks like your MC is just about where it needs to be at 6/g and I would simply keep adding the calmag. I would not recommend adding BE with the SC... SC is the proper supplement for soil, and BE is better in a hydro situation, being pure PK without all the additives for soil in the SC. If you are tempted to add more P and K I would up the SC rate just a notch, but be careful of lockouts. Right now I see none of the lockout problems associated with MC usage and it looks like you have it dialed in just about right.

 

[6thsense]

I am thinking it to be a calcium deficiency, and one that looks like it is being managed. It looks like your MC is just about where it needs to be at 6/g and I would simply keep adding the calmag. I would not recommend adding BE with the SC... SC is the proper supplement for soil, and BE is better in a hydro situation, being pure PK without all the additives for soil in the SC. If you are tempted to add more P and K I would up the SC rate just a notch, but be careful of lockouts. Right now I see none of the lockout problems associated with MC usage and it looks like you have it dialed in just about right.

Cal deficiency was my first guess . Im already at 6ml/ gal which is the max the bottle says to use . Guess ill just ride it out for now .

 

[6thsense]

@Emilya once I upped the cal mag the problem seems to be solved in 2 of the plants (pics1,2) but the 3rd plant still seems to be getting worse although it has slowed a little . I should also mention Ive been ph’ing a little higher 6.5-6.7 . These girls drink very slow also I was pretty brutal throughout veg and right after 12/12 flip with letting the plants dry out . Any possibility that has caused them to drink slower ?
Week 5 flower

 

[Emilya Green]

@Emilya once I upped the cal mag the problem seems to be solved in 2 of the plants (pics1,2) but the 3rd plant still seems to be getting worse although it has slowed a little . I should also mention Ive been ph’ing a little higher 6.5-6.7 . These girls drink very slow also I was pretty brutal throughout veg and right after 12/12 flip with letting the plants dry out . Any possibility that has caused them to drink slower ?
Week 5 flower

Being brutal as you say, while in veg, by forcing them into a strong wet/dry cycle is exactly how things should be done... I definitely do not think this has anything to do with them drinking slowly now. Also there is no need to adjust your pH in MC if you are between 8 and 5, but pH adjusting so high might be a cause of problems. I am curious what has made you want to pH at the upper end of the soil pH scale and this might be the trouble here.

Your 3rd plant might just have stronger magnesium needs than the others... keep supplenting and go to the max recommended dosage on that one for a few cycles and see what happens.

 

[6thsense]

Being brutal as you say, while in veg, by forcing them into a strong wet/dry cycle is exactly how things should be done... I definitely do not think this has anything to do with them drinking slowly now. Also there is no need to adjust your pH in MC if you are between 8 and 5, but pH adjusting so high might be a cause of problems. I am curious what has made you want to pH at the upper end of the soil pH scale and this might be the trouble here.

Your 3rd plant might just have stronger magnesium needs than the others... keep supplenting and go to the max recommended dosage on that one for a few cycles and see what happens.

I realized my ph pen needed to be calibrated again. My water is from a well and has very low ph and the pen was reading .3 high so when I thought I was ph’ing to 6.6 it was really much lower .

 

[NuttyProfessor]

Dry soil can tie up (k)
and how is the humidity if the humidity gets a bit high it can stop cal from moving out the leaf tips

Calculations from a loses soil have shown that decreasing water content resulted in

• - a strong decrease of K transport from the soil to the root,
• - a faster decrease of the K concentration at the root surface and therefore
• - increasingly steep gradients of the K concentration around the root

With the root density found in this experiment the K concentration of the moist soil (θ∼ 0.4) decreased almost equally in the total soil volume whereas in the dry soil (θ ∼ 0.1) not much change occurred in the middle between two roots.

Therefore, the rate of K uptake per unit of root decreased much faster in the dry than in the moist soil.

Potassium Deficiency Dry soils have resulted in a high incidence of potassium (K) deficiency symptoms in plants , . Dry soil reduces K uptake by slowing the movement of K from the soil solution to the plant root.

 

[6thsense]

Dry soil can tie up (k)
and how is the humidity if the humidity gets a bit high it can stop cal from moving out the leaf tips

Calculations from a loses soil have shown that decreasing water content resulted in

• - a strong decrease of K transport from the soil to the root,
• - a faster decrease of the K concentration at the root surface and therefore
• - increasingly steep gradients of the K concentration around the root

With the root density found in this experiment the K concentration of the moist soil (θ∼ 0.4) decreased almost equally in the total soil volume whereas in the dry soil (θ ∼ 0.1) not much change occurred in the middle between two roots.

Therefore, the rate of K uptake per unit of root decreased much faster in the dry than in the moist soil.

Potassium Deficiency Dry soils have resulted in a high incidence of potassium (K) deficiency symptoms in plants , . Dry soil reduces K uptake by slowing the movement of K from the soil solution to the plant root.

Humidity has been mostly high 40’s low 50’s . So you think letting the soil get too dry is my problem? And its a k def not a cal mag issue ? Interesting

 

[NuttyProfessor]

i am thinking drying the soil is starving the plants of (K) and deep flower this is what they want more of , when the soil drys outs it starving the plant of what it needs the most to finish
I let 2 of my plants dry out ( just to see ) and a few days later i got (K) on lower leaves , definitely a connection between the two

 

[6thsense]

i am thinking drying the soil is starving the plants of (K) and deep flower this is what they want more of , when the soil drys outs it starving the plant of what it needs the most to finish
I let 2 of my plants dry out ( just to see ) and a few days later i got (K) on lower leaves , definitely a connection between the two

So your suggestion would be increase the watering frequency?

 

[NuttyProfessor]

i would think plain water this round encase there is a build up , yes do not let dry as much in flower , i try to stay about 40/50% damp now , not soaked or not too dry, an air pump in the water res is good to have
This is two i just tested as i want to confirm my self , after a dry droop my lower leaves give up the (K)

let this dry too

 

[Emilya Green]

I realized my ph pen needed to be calibrated again. My water is from a well and has very low ph and the pen was reading .3 high so when I thought I was ph’ing to 6.6 it was really much lower .

Megacrop does not require pH adjustment if you are anywhere between 8 and 5 after adding the megacrop to your water. I really don't think that pH is the issue here because Megacrop doesn't require being in a narrow pH range like most synthetic nutes do... and what you have going on looks just like a simple magnesium deficiency that is very common when growing with LED lights and filtered water.

Your latest advisor seems to have some confusion as to what is going on with your plants, a potassium deficiency or a magnesium deficiency. You gave extra calmag and saw the response in two of your plants... that was the correct diagnosis. Then there is the problem that your plants are refusing to take a lot of water, yet your last advisor recommends that you give more water... so that doesn't seem to be correct advice either. To further complicate the issue, you were given a very scientific sounding study on field crops drying out that has been taken out of context to try to prove the point. Lastly, you have been also given advice to give plain water. This is contrary to how GLN advises you to use Megacrop... they strongly advise NEVER to give plain water. You now have to decide who among your advisors is leading you down the correct path and who is not. Use the clues your plants are giving you to decide which way to go.

 

[6thsense]

Megacrop does not require pH adjustment if you are anywhere between 8 and 5 after adding the megacrop to your water. I really don't think that pH is the issue here because Megacrop doesn't require being in a narrow pH range like most synthetic nutes do... and what you have going on looks just like a simple magnesium deficiency that is very common when growing with LED lights and filtered water.

Your latest advisor seems to have some confusion as to what is going on with your plants, a potassium deficiency or a magnesium deficiency. You gave extra calmag and saw the response in two of your plants... that was the correct diagnosis. Then there is the problem that your plants are refusing to take a lot of water, yet your last advisor recommends that you give more water... so that doesn't seem to be correct advice either. To further complicate the issue, you were given a very scientific sounding study on field crops drying out that has been taken out of context to try to prove the point. Lastly, you have been also given advice to give plain water. This is contrary to how GLN advises you to use Megacrop... they strongly advise NEVER to give plain water. You now have to decide who among your advisors is leading you down the correct path and who is not. Use the clues your plants are giving you to decide which way to go.

It doesn’t really make sense if cal mag cleared up the problem in 2 of the plants unless the 3rd plant has a completely different issue then the others . Also watering when the plant isnt ready doesn’t add up to me either . BUT this is only my 4 th grow and @NuttyProfessor is way more experienced then me . As a matter if fact both of you have given me very good advice in the past . This is what happens anytime I post a question on a possible deficiency I get multiple diagnosis and end up more confused then when I started lol

 

[6thsense]

Also this has happened to every grow so far to some degree so obviously im doing something wrong

 

[NuttyProfessor]

calcium (Ca++), magnesium (Mg++), potassium (K+), they bounce off each other , plain water as in nute free but the correct ph i proved it above by letting my plants dry out , i let my two smallest dry out

 

[6thsense]

Dude I appreciate your advice immensely. Youve helped me I’m the past and I know you know your stuff . I appreciate her advice too . Im not trying to start an argument here . I just want to fix this issue I keep having

 

[NuttyProfessor]

 

[Emilya Green]

Dude I appreciate your advice immensely. Youve helped me I’m the past and I know you know your stuff . I appreciate her advice too . Im not trying to start an argument here . I just want to fix this issue I keep having

I am going to duck out of this before it gets to the point of an argument. Everyone have a nice day!