Is this a zinc issue?

[SeniorMoments]

Three Gorilla Glue Auto’s grown in soil w/ 1/3 perlite.
Closet grow w/ , trust me , ample light.
Day 62 , Week 9 Fox Farm nutrients.
The plants are just about on a two day cycle now , water , feed , water...
Air temps 75* to 68*
RH 40% to 52%
There are no pests !!
The 3 plants were each trained differently , thus outward appearance is very different.
Although the plants are developing differently ( due to different training ) they are very healthy
and building buds.
The plants have exhibited a bit of tip newt burn for awhile ( which is a good thing , right ? )
But there are just a very few leafs with some damage and half a dozen that look like the photo.
Could this be a zinc issue ? If so , is it a deficit ?
Checked Pests and Problems , zinc appears to be the culprit ?
Should I even be concerned with 2 to 3 weeks left ?

 

[Emilya Green]

looks to me like a calcium deficiency, but I will wait for the others to chime in before locking that in. I would further guess that it is due to pH and I am curious where you adjust your pH to when giving your water and/or nutes.

 

[SeniorMoments]

looks to me like a calcium deficiency, but I will wait for the others to chime in before locking that in. I would further guess that it is due to pH and I am curious where you adjust your pH to when giving your water and/or nutes.

Funny u ask this Emilya.
You caught me.
My last grow I strictly used my well water and PH’d to 6.2
This grow ( experiment all around ) , I have used tap water , left sitting for approx 2 days
without adjusting PH what so ever. It is around 7.2.
With newts it drops to around 5.5.
So if PH is the issue it took 8 full weeks to show.
After 9 weeks of not adjusting PH , do you think my soil is not buffering ?
I actually did the scheduled FF flush last weekend . 3 x pot size w/ FF sledgehammer.
U think , at this late date , I should start adjusting ?

 

[Emilya Green]

Funny u ask this Emilya.
You caught me.
My last grow I strictly used my well water and PH’d to 6.2
This grow ( experiment all around ) , I have used tap water , left sitting for approx 2 days
without adjusting PH what so ever. It is around 7.2.
With newts it drops to around 5.5.
So if PH is the issue it took 8 full weeks to show.
After 9 weeks of not adjusting PH , do you think my soil is not buffering ?
I actually did the scheduled FF flush last weekend . 3 x pot size w/ FF sledgehammer.
U think , at this late date , I should start adjusting ?

LOL, thanks for fessing up.

Interesting questions... lets blow up some bro science misconceptions with your present results as proof.

So, yes, the buffers in the soil eventually do buffer the fluids you put in, even in the extremes you experimented with, but... and this is a big but...

That process doesn't happen immediately. You can't break the rules of chemistry, and so for a period of time your non adjusted nutes (or at least a portion of them) are not mobile in the soil and are not available to the plants. For that period of time while the buffers are adjusting your fluids into the range, however long it may take, your plants are running on a deficit, and they can not store away as much nutrition as they would have normally been able to, given immediately available nutrition broken free of its salt chelation bonds. Its not much of a deficit, but over time, and near the end of the grow, any regular deficit can start to show. All things in a grow are cumulative.

Other than that, you are doing fine, and it is a credit to FF nutes that this is all that is happening. I decided in my early growing days to accept the common advice to pH adjust to 6.5, and over time realized that I was getting a consistent molybdenum deficiency at week 6 of the grow, like clockwork. Molybdenum? Seriously? It drove me crazy until I realized that at 6.5 the pH was too high to pick up much at all of this micronutrient, and it wasn't until late in the grow when it presented itself, and very strongly at that! I consistently reduced my pH to 6.2 so that we could see the low end of the range before the buffers and drift drove the pH up, and from then on when using FFOF soil and adjusting to the low end, that fixed it... I never saw that deficiency again.

Ph is important, don't believe all the so called experts telling you that it isn't. Sure, you can get by with not pH adjusting in several soils that are out there, but please think about what it is that they are promoting. These soils are made for people who don't want to invest in pH meters or even understand what a pH is... they are made for automatic, lazy gardening by non experts. You get what you put into it in most things in life, and it is no different here. You can use shortcuts if you want, but then you also shortcut your grow. There are right ways to do things and wrong ways and a thousand ways in between. Your grow will adjust accordingly.

At this point I would adjust pH and I would supplement with some calmag to offset the deficit up until the next to last watering. The plant is stealing calcium from the upper leaves right now to supply what is needed to the buds... and you don't want them to run out of this supply before they are done.

 

[SeniorMoments]

LOL, thanks for fessing up.

Interesting questions... lets blow up some bro science misconceptions with your present results as proof.

So, yes, the buffers in the soil eventually do buffer the fluids you put in, even in the extremes you experimented with, but... and this is a big but...

That process doesn't happen immediately. You can't break the rules of chemistry, and so for a period of time your non adjusted nutes (or at least a portion of them) are not mobile in the soil and are not available to the plants. For that period of time while the buffers are adjusting your fluids into the range, however long it may take, your plants are running on a deficit, and they can not store away as much nutrition as they would have normally been able to, given immediately available nutrition broken free of its salt chelation bonds. Its not much of a deficit, but over time, and near the end of the grow, any regular deficit can start to show. All things in a grow are cumulative.

Other than that, you are doing fine, and it is a credit to FF nutes that this is all that is happening. I decided in my early growing days to accept the common advice to pH adjust to 6.5, and over time realized that I was getting a consistent molybdenum deficiency at week 6 of the grow, like clockwork. Molybdenum? Seriously? It drove me crazy until I realized that at 6.5 the pH was too high to pick up much at all of this micronutrient, and it wasn't until late in the grow when it presented itself, and very strongly at that! I consistently reduced my pH to 6.2 so that we could see the low end of the range before the buffers and drift drove the pH up, and from then on when using FFOF soil and adjusting to the low end, that fixed it... I never saw that deficiency again.

Ph is important, don't believe all the so called experts telling you that it isn't. Sure, you can get by with not pH adjusting in several soils that are out there, but please think about what it is that they are promoting. These soils are made for people who don't want to invest in pH meters or even understand what a pH is... they are made for automatic, lazy gardening by non experts. You get what you put into it in most things in life, and it is no different here. You can use shortcuts if you want, but then you also shortcut your grow. There are right ways to do things and wrong ways and a thousand ways in between. Your grow will adjust accordingly.

At this point I would adjust pH and I would supplement with some calmag to offset the deficit up until the next to last watering. The plant is stealing calcium from the upper leaves right now to supply what is needed to the buds... and you don't want them to run out of this supply before they are done.

My wife would say there is not a lazy bone in her husbands body.
So , that played no part in me making a decision to not PH.
There is a lot of info out there disputing the importance of PH , in soil , so I thought , why not.
Try it. I am already breaking many of the rules growing these auto’s.
I think I have to agree with your assessment.
It is logical and you offer an excellent example to back up your reasoning.
I already watered this morning so I will adjust at the next feeding.
Should I go ahead and do another flush at that time ?
It would be a week early per FF schedule .
Thank you for the help.

 

[Emilya Green]

no, the flush is just to remove the salts and you did that.... just continue on and next grow will go better now that you know. There is another adage that I like a lot that applies here: Trust nothing, verify what you can.