Calcium deficiency? Leaf Septoria? Help! (flowering stage)

thekall55 · May 7, 2020

Hi everyone,

I have these brown spots appearing for about the last two weeks. Plants are 9 weeks old and are flowering now.

Another plant i started at the same time was harvested, and I saw the same thing happening to that plant so I harvested it about a week or two early out of fear. Is this Calcium deficiency? Some kind of fungus or pest?

This plant has flowered way slower than the other one I harvested.

Lights: 1000W full spectrum LED
Watering: once every 2-3 days, when soil is dry, I soak through and wait till its dry again. Nutrients added every other watering (fox farm trio) at half strength.
PH: PH strips show my tapwater is 7.0 or so, a slurry of the soil and tap water is about the same.

Is this calcium deficiency or some kind of fungus? I checked for spider mites, and there are no webs anywhere and it doesnt seem to match my pictures.

Did I harvest the other plant too early for no reason? Despite being started at the same time, the other plant was weeks ahead maturity wise and you guys could see my other post about that plant asking if it was ready to harvest!

thekall55 · May 7, 2020

Worried about this plant... will this ruin the harvest? Its 4 feet tall now.

Should I remove the affected leaves?

Moshmen · May 7, 2020

Looks like it’s locked up to me? Do you water till runoff? Have you cked ppm or E.C. ? Wait for someone with a little more knowledge but looks like high ppm and high ph causing calcium to get locked out

thekall55 · May 7, 2020

Moshmen said:
Looks like it’s locked up to me? Do you water till runoff? Have you cked ppm or E.C. ? Wait for someone with a little more knowledge but looks like high ppm and high ph causing calcium to get locked out

This is what I was thinking... I water till runoff yeh. I have not checked ppm or E.C... I dont have the means to do so.

Im gonna invest in a good PH probe for this I think. The strips suck.

The other plant was treated the same way, and started developing the same spots but was further along so I just harvested it.

growsince79 · May 7, 2020

Moshmen said:
Looks like it’s locked up to me? Do you water till runoff? Have you cked ppm or E.C. ? Wait for someone with a little more knowledge but looks like high ppm and high ph causing calcium to get locked out

+1

Moshmen · May 7, 2020

Lots of guys use the strips but a cheap ppm meter will be a good friend !
Ultimately ppm and E.C. are the same thing just different ways to measure conductivity

thekall55 · May 7, 2020

growsince79 said:
+1

So what do you recommend? Acidifying the water next time down to like 6.2-6.5?

thekall55 · May 7, 2020

Moshmen said:
Lots of guys use the strips but a cheap ppm meter will be a good friend !
Ultimately ppm and E.C. are the same thing just different ways to measure conductivity

For sure. So what do you recommend? Acidifying the water next time down to like 6.2-6.5? Also the nutrients I am using dont say they have Calcium in them.

Mg, B, Cu, Fe, Mn, Zn but no Ca

Can I use 1M HCl to acidify? Im a chemist and have dilute HCl from my lab and figured just titrate the water until its lower PH unless I should use some other kind of specific product for plants for acidification/alkalinity

Edit: tap water is 7.0 and runoff (through the pot out the bottom) is closer to 7.5

growsince79 · May 7, 2020

thekall55 said:
For sure. So what do you recommend? Acidifying the water next time down to like 6.2-6.5? Also the nutrients I am using dont say they have Calcium in them.

Mg, B, Cu, Fe, Mn, Zn but no Ca

Can I use 1M HCl to acidify? Im a chemist and have dilute HCl from my lab and figured just titrate the water until its lower PH unless I should use some other kind of specific product for plants for acidification/alkalinity

Edit: tap water is 7.0 and runoff (through the pot out the bottom) is closer to 7.5

Yes or you could use lemon juice.

thekall55 · May 7, 2020

growsince79 said:
Yes or you could use lemon juice.

Will the fact that my nutes dont add additional Ca be an issue?

Also, good idea to remove affected leaves?

needshelpguy · May 7, 2020

Yes you need to be adding ca, i wouldnt be removing leaves unless they fall off easily in your hand as the plant will be drawing the little calcium it has from those leaves

MIMedGrower · May 7, 2020

Looks like too much nutes and too frequent watering has locked out calcium.

Flush and feed only 25% strength back if needed and wait for improvement. Do not water til pot is very dry. Im guessing dryer than when you have been watering so far.

And if you use the third organic bottle as directed the micronutes are in there.

MIMedGrower · May 7, 2020

I meant to add you need to know your runoff ec (ppm). If it is very low uour plant is hungry and if high locked out. Should be monitored every time. Ph is way overstated as cause on these forums. Tap water does not change buffered potting soil ph.

Moshmen · May 7, 2020

MIMedGrower said:
I meant to add you need to know your runoff ec (ppm). If it is very low uour plant is hungry and if high locked out. Should be monitored every time. Ph is way overstated as cause on these forums. Tap water does not change buffered potting soil ph.

Agreed ! Sorry gonna jack ur thread for a second, I’m having an issue with low ph in the promix from salt build up I believe , even after a good flush it seems to still be low do you think adding Some lime to the mix would help or hurt? By masking the real problem?

Beachwalker · May 7, 2020

thekall55 said:
This is what I was thinking... I water till runoff yeh. I have not checked ppm or E.C... I dont have the means to do so.

Im gonna invest in a good PH probe for this I think. The strips suck.

The other plant was treated the same way, and started developing the same spots but was further along so I just harvested it.

Try these
regarding septoria, I had a big issue with it years ago, can be tough to diagnose

beat it with copper spray and sulfur burning I can't say for sure it's septoria but brown circle with a black ring around it can be septoria

What's your humidity, do you spray the plant, your recent runoff readings and other information like that would help

Beachwalker · May 7, 2020

Moshmen said:
Agreed ! Sorry gonna jack ur thread for a second, I’m having an issue with low ph in the promix from salt build up I believe , even after a good flush it seems to still be low do you think adding Some lime to the mix would help or hurt? By masking the real problem?

Try dolomite, tbsp per gallon in soil but might try half that at first in promix, I water it in slowly

MIMedGrower · May 7, 2020

Moshmen said:
Agreed ! Sorry gonna jack ur thread for a second, I’m having an issue with low ph in the promix from salt build up I believe , even after a good flush it seems to still be low do you think adding Some lime to the mix would help or hurt? By masking the real problem?

What were the final ppm’s? Also the low ph is the runoff ph so if there was excess nutes being flushed the runoff can read low.

I see this too and the ph is always back to about 6.2 the next time i water/feed after flushing.

I added lime to a couple when i first noticed this problem myself and it has raised the general ph a little.

The pots i didnt add lime to both went back to normal by next watering anyway.

Pro mix also reads very low off the bale until the lime charges in about a week after watering in.

And mine is showing about 500ppm 1.0ec out of the bag even hough it has no nutes. That also seems to correct itself after a watering or two.

Moshmen · May 7, 2020

MIMedGrower said:
What were the final ppm’s? Also the low ph is the runoff ph so if there was excess nutes being flushed the runoff can read low.

I see this too and the ph is always back to about 6.2 the next time i water/feed after flushing.

I added lime to a couple when i first noticed this problem myself and it has raised the general ph a little.

The pots i didnt add lime to both went back to normal by next watering anyway.

Pro mix also reads very low off the bale until the lime charges in about a week after watering in.

And mine is showing about 500ppm 1.0ec out of the bag even hough it has no nutes. That also seems to correct itself after a watering or two.

Sometimes I even feel I should be feeding more! Lol so at leSt I know I’m goin in the right direction , thank you

thekall55 · May 7, 2020

Beachwalker said:
Try these
View attachment 970101 regarding septoria, I had a big issue with it years ago, can be tough to diagnose

beat it with copper spray and sulfur burning I can't say for sure it's septoria but brown circle with a black ring around it can be septoria

What's your humidity, do you spray the plant, your recent runoff readings and other information like that would help

View attachment 970103 View attachment 970104

Humidity is between 38 and 40%. PH of the runoff was 7.0

thekall55 · May 7, 2020

MIMedGrower said:
Looks like too much nutes and too frequent watering has locked out calcium.

Flush and feed only 25% strength back if needed and wait for improvement. Do not water til pot is very dry. Im guessing dryer than when you have been watering so far.

And if you use the third organic bottle as directed the micronutes are in there.

Dont think its leaf septoria?

Calcium deficiency? Leaf Septoria? Help! (flowering stage)

Calcium deficiency? Leaf Septoria? Help! (flowering stage)

thekall55

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