Terminal calcium deficiency?

Rurumo

Well-Known Member
What are your temps like in there, and do you have any fans blowing directly on the plant?
 

McShnutz

Well-Known Member
Looks like Magnesium to me.
Calcium is an immobile element. It's ALWAYS taken from the oldest growth to supplement to the newest. It appears as spots.

Magnesium is mobile and is take from all over. Growers generally see it on the upper portions of their plants because it's an essential element for photosynthesis. PPFD levels are always higher more towards the top of the plant. (Closest to the light) and consequently the photosynthesis activity is highest in said leaves. This is where your deficiency is most likely to show its ugly face.

Epson Salts @ 1tablespoon/gallon of h20.
Rest easy, Magnesium sulfate will not change your pH(h20) or (KCI). Just don't over apply it as it can antagonise other elements.

Alternatively it can be foliar sprayed. Your very early into flower set and it won't affect the buds. Don't use a wetting agent.
Spray @ 1.5tsp/gallon
 

speedwell68

Well-Known Member
Looks like Magnesium to me.
Calcium is an immobile element. It's ALWAYS taken from the oldest growth to supplement to the newest. It appears as spots.

Magnesium is mobile and is take from all over. Growers generally see it on the upper portions of their plants because it's an essential element for photosynthesis. PPFD levels are always higher more towards the top of the plant. (Closest to the light) and consequently the photosynthesis activity is highest in said leaves. This is where your deficiency is most likely to show its ugly face.

Epson Salts @ 1tablespoon/gallon of h20.
Rest easy, Magnesium sulfate will not change your pH(h20) or (KCI). Just don't over apply it as it can antagonise other elements.

Alternatively it can be foliar sprayed. Your very early into flower set and it won't affect the buds. Don't use a wetting agent.
Spray @ 1.5tsp/gallon
That was a really good post. I actually learned something. I have noticed people describing elements mobile and immobile and never really understood it.

Thanks.
 

swantip

Well-Known Member
What are your temps like in there, and do you have any fans blowing directly on the plant?
This is an important question. Also what type of lights?
24-25C(74-78F) rh:55-60% but i had humidity problems early on,before i go and buy a humidifier. 600W HPS. I also have an oscilating fan which blows on the top of the cola a bit,I dont have any more room to fit everything.This is an autoflower and its growing very vigorously its 115cm(45in) and only 40 days since sprout,so this really surprised me.
 

Kassiopeija

Well-Known Member
Calcium is an immobile element. It's ALWAYS taken from the oldest growth to supplement to the newest.
that's wrong, Ca cannot be re-mobilised (better: retranslocated) which is the reason why a Ca-def results in stunted chlorotic shootgrowth, the necrotic spots appear somewhat later when the leaf becomes dysfunctional. And why you need a steady supply of Ca in water.
Mg is mobile and that's the reason why it's taken from the older leaves. In times of need, plants disassembles lower chlorophyll, attach the minerals to transporter-proteins, and feed these into the phloem where they can travel up or down.
But pH problems (xylem not neutral) can actually "sabotage" the ability to retranslocate nute-ions, then mobile nute defs can also appear mid or top the plant. The xylem's and phloem's pH is apart by +-1.5 - 2.0 and this creates a "pressure" to make it possible.

This is where your deficiency is most likely to show its ugly face.
only in the case of photodestruction from too high irradiance, then - and with a true Mg def, the leaves will show striped chlorosis, unlike N or S def, which will affect the complete leafcolour
 
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