Auto Glueberry OG infirmary

[Z_Burp]

Problem: Yellow spots followed by brown spots then foliage dying

Medium/grow method: OF, soil pH 6.5

Feed: and supplements used: 1/4 strength open sesame, beastie bloomz, Calmag 1 ml/L

water source: tap, pH'd to 6.5 after nutes added

Strain/age: Auto Glueberry OG day 55, symptoms occurred two weeks ago

light used: LED

Climate: 40% RH, indoor

Additional info: I first assumed it was a cal/mag dificiency, but now I'm leaning more towards manganese. Unsure now.

Thanks for the help!

 

[Heavily Medicated]

You need to post pics taken under natural or white light. Pics taken under the grow lights just doesn't give the needed info.

 

[Z_Burp]

They cannot be taken outside to be viewed in natural light, unfortunately. The white light will have to do. I must have clicked the wrong last picture.
Sorry about that!

 

[Waira]

Z'-- Hmmm, could be a couple things,.. first, how did you check actual in-pot soil pH? ... 6.5 is great, but the accuracy and method of this is something I need to confirm, as it's a big clue,... the symptoms sure do look like P defc., though Ca defc. can sometimes mimic it... Now, you say you're using both OS and BB at 1/4 strength together? these are very powerful boosters (I use them myself sometimes), I don't think both are called for; are they going in at 1/4 strength each, or half and half of each at a total of 1/4 str.?
...here's the puzzle: too much P can cause Ca uptake issues, which could lead to Ca defc. showing even if there Ca in there,.. are you using a Ca-mg supplement?
....or, if the soil pH is actually off enough, acidic side, it can start to lock out P as well,... In fact soils, OF especially, have been showing badly acidic pH right out of the bag; not all, but it's alarmingly common,...
.... Mn defc. is quite rare, and even under acidic off-pH soil conditions, it remains available,.. so if it's Mn defc. it's a simple lack-of type defc.,... the fix there is a micronutrient supplement, like Earth Juice Microblast....

>> pending the soil pH confirmation, use of/dosage of Ca-Mg, and what you other nutes are, we'll pin it down better and recommend a course of action!

 

[Z_Burp]

I tested the soil with an in ground probe which reads 6.5 and I tested the runoff which reads 6.5 with a pH pen. I also try to be meticulous during watering and feeding to be at 6.5 pH.
The only nutrient that I've used in the last two weeks was cal/mag at 1 ml/L every other watering pH at 6.5. (I misunderstood the nutrient request, I put in all I've used to date)
Maybe there in lies the problem? BB is 0-50-30 and I stopped using it when I noticed the yellow/brown spotting.
Thanks for your help, @Waira @Heavily Medicated

 

[Waira]

..just curious, was it an Accurate 8, or a skinny rod type probe? And the pH meter, calibrated recently? I like that you got consistent readings from both,... my concern is that the skinny probes are notoriously inaccurate, and the pH meters are touchy devices, going out of tolerance easily and fast sometimes depending on it storage and care,... I gotta ask mate! so many times bad readings muck up the fix- - sounds like your on it though.. So, you used no grow nutes, just the bloom boosters and Ca-Mg? Hmmm, weird,.. the BB and OS have some micro's in them including Mn,...no regular bloom nutes? ... the Ca-Mg dose has been pretty mild,... what's the wtaer source, tap or RO/Di? ..looking for other Ca inputs here,...

 

[Z_Burp]

..just curious, was it an Accurate 8, or a skinny rod type probe? And the pH meter, calibrated recently? I like that you got consistent readings from both,... my concern is that the skinny probes are notoriously inaccurate, and the pH meters are touchy devices, going out of tolerance easily and fast sometimes depending on it storage and care,... I gotta ask mate! so many times bad readings muck up the fix- - sounds like your on it though.. So, you used no grow nutes, just the bloom boosters and Ca-Mg? Hmmm, weird,.. the BB and OS have some micro's in them including Mn,...no regular bloom nutes? ... the Ca-Mg dose has been pretty mild,... what's the wtaer source, tap or RO/Di? ..looking for other Ca inputs here,...

It's dual rod type soil probe that has an analog type dial on the front similar to the one below:

The pH meter is from Amazon and is rated as accuracy +/- 0.1, I rinse in distilled water after each use and put it back in it's case when I'm done:

I did a two point calibration two/three months ago using General Hydroponics 4.01 pH and 7.0 pH calibration solution. I recall I did it before I started my Ice Cool Auto and Auto Glueberry OG.
I use regular tap water that's been sitting out for 24+ hours before I use it to water. I also get the water pH to 6.5'ish before watering if there's no nutes in it and also after adding nutes. My tap water runs 7.8-8.1 pH out of the faucet. I don't have a TDS meter so I can't give you that info, sorry.

Last four weeks feeding schedule (watering between feedings with 6.5 pH as needed):
2/12/17 - 4 L water, 1 ml/L cal-mag, 1/4 tsp of OS, pH 6.4
2/19/17 - 4 L water, 1/4 tsp of BB, pH 6.3
2/26/17 - noticed the spotting here, but I think there was some I didn't see on the back side of the lady before I noticed - 4 L water, 1.5 ml/L cal-mag (thought it was cal-mag def) forgot to write down pH
3/5/17 - spotting worse, leaves browning/curling/dying - 4 L water, 2 ml/L cal-mag, pH 6.3
3/12/17 - PANIC, didn't write down a thing. I recall 2 ml/L cal mag...

She's scheduled to be finished around April 10, so I've got a little more than 3 weeks left on her.

Ask away, be brutal if you have to, this is important stuff!

Again, thank you very much for your help @Waira @Heavily Medicated

 

[TheJesus]

Do you have a University or Dnr extension office near you? I often will take my soil to a local school and have it run through a MAS spectrometer or a soil analysis lab. This might sound odd or loops but it will tell you EXACTLY what is going on in your soil. See if you have a EXTENSION to your university. Thats what it will be called.

 

[Z_Burp]

Do you have a University or Dnr extension office near you? I often will take my soil to a local school and have it run through a MAS spectrometer or a soil analysis lab. This might sound odd or loops but it will tell you EXACTLY what is going on in your soil. See if you have a EXTENSION to your university. Thats what it will be called.

There is an Oregon Department of Geology and Mineral Industries about an hour away, I don't know if that's reasonable with such a short amount of time left for her? What part of the soil in the "soil column" in the pot should I take, and how much? I'm thinking along the lines of a core sample?
I will definitely test my next batch of soils, though! Thanks for the reply @TheJesus!

 

[Waira]

...OK, the meter needs more frequent calibration, maybe it's still close, maybe not,... One thing that messes with them is not storing it in the right solution, but not all call for it,.. see if yours does; drying out can knock it out of calibration too,... I'm dubious about the probe, but perhaps that dual probe unit is better than the single probe skinny types I've tested next to the A8 unit... that probe is worth it's weight in gold, so consider scoring one! You've been solid for pH'ing inputs, so that goes a long way to keeping the soil pH in line.
... So, no regular nutes at all not grow, or bloom,.. the problem is OS and BB are supplementary bloom boosters, and not nutritionally complete, and I don't like the ammonium N, this tend to make them very acidic, which during uptake by the roots, also adds acidity... Often there can be more subtle deficiencies, but not show it by outward symptoms... sometimes they show indirectly by other nute defc.'s... several are involved with the metabolizing with others,... You're getting close to wind down here, but I'd still consider getting a dedicated primary bloom nute, and/or a micronute supplement,.. raise the Ca-Mg to full dose conc.; these girls have so nice size, and are really sucking upo the PK, so meantime, you can blend the OS and BB together to get better nute element coverage (OS has S in it very important for terpene building!) and since it's over a gal of water total, try upping it to 1/3-1/2 tsp total,... Let's see if the elevate PK and Ca-mg stop symptom progression after a few days,...