Septoria aka. brown leaf spot here.. (picture heavy)

Beachwalker

Well-Known Member
All things brown leaf spot, leaf drop septoria fungus here..

Wet fall in parts of North America and septoria is exploding!

Let's talk about it here, as it can be very hard to diagnose and it looks differently at different stages, imitating many different common plant issues!

You'll also notice there's not much info about it indoors on the internet for some reason, but let's try to change that here..

This brown spot with the ring around it is often the first, and most specific indicator of septoria (and very easy to miss)20180612_034240.jpg

.. the rest of these pictures are also septoria, tho often initially misdiagnosed as calcium, mites and/or other more common issues
 

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Jypsy Dog

Well-Known Member
All things brown leaf spot, leaf drop septoria fungus here..

Wet fall in parts of North America and septoria is exploding!

Let's talk about it here, as it can be very hard to diagnose and it looks differently at different stages, imitating many different common plant issues!

You'll also notice there's not much info about it indoors on the internet for some reason, but let's try to change that here..

This brown spot with the ring around it is often the first, and most specific indicator of septoria (and very easy to miss)View attachment 4154420

.. the rest of these pictures are also septoria, tho often initially misdiagnosed as calcium, mites and/or other more common issues
NO PLACE on this PLANET is it FALL. Too many Chemtrails dude?????
https://magazine.grasscity.com/yellow-leaf-spot-and-marijuana-plants-2227/
 

hotrodharley

Well-Known Member
The information is still relevant. I am experiencing septoria for the first time in my life. Interior Alaska so started indoors. Electric is sky high here so I moved outside as soon as it stopped freezing and days got longer. Grow bags using peat mix. I know what I'm doing for the most part and use cal mag from the start in this medium. I also use inoculants like Great White or Mykos.

Temps dropped, it rained, it stayed cloudy a lot. Then I start getting these spots I think look like calcium deficiency. No way with pH treating water with a PPM of 145 and mostly calcium.

I'm a desert rat from west Texas and southern New Mexico. I had to start asking pro growers here. One immediately mentioned septoria and that my other plants might soon get it if not treated and he was right

Thanks for posting for others. I'm glad I didn't start hitting a deficiency that doesn't exist.
 

Beachwalker

Well-Known Member
catch it early this kicks it ass!!!once one knows what to look for its very easy to wipe out low rh an good fresh air never get it indoorView attachment 4154531
.. I wouldn't think you could use that on budding plants??

I've sprayed neem oil on budding plants and the buds were crap, I threw whole plants right in the hash box

Currently I've got a few spots on two strains in the veg tent too, everything got a spray of neem oil today but I don't use it in flower
 

Beachwalker

Well-Known Member
The most effective treatment I have found is a sulfur burner used every other day, after a 3 day in-a -row start to the treatment.

On alternate days I spray baking soda at a ratio of 1 teaspoon/quart of UN-pH'ed water, as the purpose of this is to raise the ph, be sure to get the underside of the leaves heavily as well as the tops

In veg tent I spray neem oil once a week and baking soda twice per week

I have never used the liquid copper spray, I would have no problem using it in veg, but would personally not use it in flower.

Ultimately and soon I'm going to need to invest in a larger dehumidifier unit, however I am close to my max draw for electric use in my grow room and that, aside from the prohibitive cost is also a consideration, but I have no alternative if I want to grow in the often swampy New England weather (I'm between a saltwater marsh and the ocean)
 
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Beachwalker

Well-Known Member
  • Air Movement
It's critical..! ..in my five-by-five in addition to an inline extraction fan and obligatory clip fan blowing between the light and the plant tops I have one 9 inch high velocity fan on the floor blowing one way and on the other side I have another 9 inch high velocity fan blowing the other way (both on low setting) so there's always steady circulation throughout the whole tent
 

Beachwalker

Well-Known Member
"I'm glad I didn't start hitting a deficiency that doesn't exist"

That's a problem because you start chasing calcium and then you think is it too much or is it to little ..what's going on here? Maybe it's magnesium, better flush, maybe my meter is off ..on and on it goes?! And meanwhile you're up to your ankles in dead leaves! :wall:

And when they do figure it out, when you look it up online all it talks about is septoria outdoors ?? ..but it happens indoors too!, just like pm happens indoors too, It's conditions that cause it, humidity is frequently above 60% here, often above 80% for days on end and it doesn't even have to be raining!
 
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thumper60

Well-Known Member
.. I wouldn't think you could use that on budding plants??

I've sprayed neem oil on budding plants and the buds were crap, I threw whole plants right in the hash box

Currently I've got a few spots on two strains in the veg tent too, everything got a spray of neem oil today but I don't use it in flower
I agree but!! the trained eye would see it way before flower, pretty much if u got it in budding the plant is fucked theres something wrong with ya environment if ya getting it indoor it needs long periods of high rh to spawn:hump:
 

Beachwalker

Well-Known Member
I know, I have never got it this early, it's been a very wet and cold spring ..but no excuses! I should have been watching for it, and doing some preventive sulfur burning too but usually dont see it til late August into the fall?

I'm looking at large dehumidifiers now, this little one that I use in the drying room obviously isn't cutting it
 

Beachwalker

Well-Known Member
20180624_234757.jpg Sorry for the yellow lights but pic is just to show there's no septoria visible in either tent right now, to illustrate that it can be stopped with alternate days of sulfur burning and baking soda spray

Now I'll only burn once every 3 days for an hour and may or may not spray depending on what I see

Most of the damage is done before you even see it, and it does take awhile to get the handle on it, but it can be stopped cold.

I would add the humidity in the tent reached 77% today and it's still raining now
 
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Beachwalker

Well-Known Member
1529932133578287185565.jpg Still raining, still humidity in the 70 and 80% range, still no septoria visible in either tent :clap:

the White Rhino X mazar which was most affected (next to the remo chemo which seemed to have little resistance and has been removed) is showing no signs of septoria

The White Rhino cross back left just got an extra treatment of neem oil spray, it's a favorite strain of mine and I want to keep the mothers in best condition!
 

Beachwalker

Well-Known Member
So I suspect yet another flowering garden being torn down due to septoria?!

Even if I spend the 200 - $250 today for an adequate dehumidifier how will I run it with my lights, AC, fans and miscellaneous on ?

I am near comfort level with my electricity now, it's not worth it to me.. going to be close to a hundred today with high humidity I can barely run my 1000 hps on 400! (haven't had it above 400 for a week) and I'm still barely handling the heat with a proper exhaust system (440cfm)

I'm likely pulling down x amount of plants that have just started to flower for about 2 weeks, but I still have clones of everything..! :mrgreen: no problem keeping small veg plants healthy, septoria does not seem to affect them

I also have two plants that are maybe 2 or 3 weeks from finishing, I may throw both in a room that doesn't get much use, they'll finish or not, one is Gunslinger which I was looking forward to working with but I'm not going to run anymore Greenpoint gear so it doesn't matter now, the other one is a White Rhino × mazar that I do care about, however I have generations of it backed up (it's been running for a while, good smoke!) that's actually doing really well fighting the septoria, much better than the Gunslinger

  • The reason I'm doing this is I've just noticed septoria on a couple leaves of least two newly flowering plants (no great shock) and I am not going to be chasing this with neem sprays and this and that, not worth it to me, however I'm going to give it till the weekend to make make a final decision on it, but I'm 90% going to tear it down

Regardless when I come back this in September with a proper dehumidifier, the AC will not be needed, so that will actually work until next summer (then the same old same old again).

Hopefully by then I can find a Cannabis friendly electrician who will work for trade?

.. Plus a friend has a beautiful house on a scenic New Hampshire Lake and I want the freedom to be able to leave and go spend time this summer on the lake, she's a school teacher off all summer, so Don't Cry For Me Argentina I don't give a rat's ass, to be honest. Things come and go man, that's all it is Jim.

Edit* actually now that I've got nothing to lose I'm going to try that liquid copper fungicide on these plants that are just barely starting to flower (I would not use it much past current point) should have used it today instead of the neem but I'm just thinking about it now, I like to experiment so if I do I'll come back and update
 
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