WTF, overnight Ca/K def, burn?

[D350]

HavingNorthern light in soil, 3 weeks from repoting, under 3x 600W MH, at night it changes to 2x400W. Temperatures were pretty high last days, but not last 4. Temps were around 28C, before even got to 35...but that was one week ago. I have humidifers, so the RH is good, from 45-65,even more sometimes. Pots are 20lit, soil is good, new, for flowering plants, with some perlite.

Now for the problem. two days ago I sprayed them with canna cure and Ortus(against spider mites). I also watered them with 1/3strenght Canna Vega+cannazym+rhizotonic.
The next day the new small leaves were twisted downwards and all curly looking. Ok, I watered them with water+dash of canna flush (scared of nute burn). The next day they were like this - see photo!
I got this horrible spots and stuff, just in one day!
Ph of water is around 6,5

What happened? Nute Burn? Too much K in Terra Vega caused Ca def? Is it calcium deficency or K def? Or just nute burn? I'm pretty desperate right now, I read and study and could not explain, what happened.
Any help is greatly appreciated.

BTW, I flushed them with around 12lit PHed water each, could not use more... runoff was around EC 3...thats with all the dirt inside...

Thank you!!!

 

[RedBeardy5]

The brown spotting looks like a calcium problem but I bet your ph is off or lockout. The leaves are pointing down so maybe your medium is over watered. What are you growing in, ph, ppm, temp, and how oftn do you water?

 

[vapor]

how strong was the pesticide? and is it phytotoxic?
light on or off?
wetting agent?

 

[canna woop!]

Flushing is not a efficient method, it only targets a symptom of the problem, that is high soluble fertilizer levels in a medium that are not being uptaken. The problem is actually the medium is saturated with external fertilizer that is reacting with the mineral elements already in the soil. Things were relatively ok before you fertilized (and flushed or w/e), frets are the weakest link here

Edit just saw pesticide, that too. Thank vape

 

[D350]

I was really careful not to overwater...
Medium is soil for plants, it's been proven before, my friend grows in it without issues.
Pesticide I used before, no issues. It is agricortural, for grapevine etc. Used reccomended dosage.
I semi flushed them, with about half the volume of soil (water).
I think my Ph is ok, I calibrated my chinese PH meter one week ago...
Why are small leaves so terribly wrinkled/curled? Should that point to Calcium problem?

SO, WHAT SHOULD I DO?
Spray them with calcium? Is it Calcium def-lockout?
Something else?

Thank you for your answers!

 

[resinryder]

What is your ph adjusted to when you water?
what is the EC of the nute mix before feeding?
If you have a runoff EC of 3 you have some serious nute buildup in the pot. Way too high.
Do you feed every watering or feed, water, feed, etc?
Also, keep in mind that recommended dosages on pesticide bottle, and even nute bottles for that matter are not for cannabis. Too much can and will mess the plants up. You can always add more if needed but you can't take it away after the fact.

 

[RedBeardy5]

what do the roots look like?

 

[Storm Shadow]

Foliar Spray Damage

 

[mack 10]

well I just typed out loads then poof, gone so here's the quick version.

you said your runoff was ec 3? do you mean 0.3 ec or 3 ec? if its 3 ec flush for your life, lol.

above 32 .C and your plants will put more energy into sweating than it can drink, then you added more nutrients/pesticides which just adds to the problem.
if you look at your plant the leaf egdes are burnt usually this is usually caused from the room being too dry and hot.
the new growth is twisty= mobile nutrient problem, micro nuts locked out? or/and pH possibly locked out too?
mack

 

[ozzieAI]

holy fuck...sorry to see man...

what do the roots look like?

i have the same question...

Foliar Spray Damage

yeah this is very likely...in whole or part...

you said your runoff was ec 3? do you mean 0.3 ec or 3 ec? if its 3 ec flush for your life, lol.

abso fucking lutely....

seaweed is a good plant tonic/conditioner....

wish you all the best...

 

[bobman]

Foilar spray with light on and heat. Especially since it happened overnight. That growth is not right and can be caused by that. Just dont go chasing your tail right not with ec and ph. Let everything settle down and keep a close eye on it over the next few days. It may get worse before it gets better but if things start really going down hill fast I would repot into some fresh soil. I have saved a few plants that way and I believe will be a better option then trying to keep watering to correct an internal problem. Last thing they need now is more water. Remember things take time in soil.

 

[D350]

Foilar spray with light on and heat..

Thank you for advice. What should I spray them with? Ca , Ca/mg or light fertiliser? Or water...?

Thank you

 

[bobman]

Sorry, I was referring to what caused that in my opinion. For it to happen so quickly that combo had to be the culprit. Just relax its kind of a waiting game now. Just keep an eye out for new growth then u will be on ur way. If things start going down hill fast then worry about the next step. Changes in soil take time its not going to happen overnight and the plant is kind of in shock right now. As long as things dont start really getting worse I should be fine. Its going to be ugly for a little no changing that. On my opinion they will be fine u should see some plants I have saved makes that look like a beauty queen. The key is not to try doing to much if worse comes to worse a repot into some fresh mixhas always worked for me that would be my next step if things start getting bad. But I dont think u r going to get there. Just take ur time and let the plant do its thing now.

 

[bobman]

Btw go have a beer and a joint and dont worry about it. U are not going to find the answer reading or studing u r just going to drive urself crazy. It will be fine. Get those temps down tough and dont spray that shit again. With that wicked leaf curl they are not liking something right now. Repotting would be my next step but give it some time. I have no idea what u used but dont so that again for spray or feed. Keep everyine pisted so u can help the nexr guy.

 

[D350]

Sorry, I was referring to what caused that in my opinion. For it to happen so quickly that combo had to be the culprit. Just relax its kind of a waiting game now. Just keep an eye out for new growth then u will be on ur way. If things start going down hill fast then worry about the next step. Changes in soil take time its not going to happen overnight and the plant is kind of in shock right now. As long as things dont start really getting worse I should be fine. Its going to be ugly for a little no changing that. On my opinion they will be fine u should see some plants I have saved makes that look like a beauty queen. The key is not to try doing to much if worse comes to worse a repot into some fresh mixhas always worked for me that would be my next step if things start getting bad. But I dont think u r going to get there. Just take ur time and let the plant do its thing now.

Damn, should have read it better, damn pot.
Soooo....I sprayed them with cal/Mg yesterday, and it looks like it did not harm them... I lowered light output from 3x600 to 2x400, temperature now is around 25C.
Right now I'm guessing I burn them with fertiliser and had ph too low (my crappy chinese PH meter was 0,5 off, so guessing water was below 6 PH)
I'll wait a couple of days now and see, how it goes.

Thank you

 

[Seal-Clubber]

Phos burn and over-watered.

 

[bobman]

Maybe but I dont think so. In a well buffered soil ph should not be an issue unless u are way off or something crazy happens. Now as far a nute burn maybe but the location and coloration of the marks dont lead me to that conclusion. In the future just be careful what u spray on them and how u spray. Always test a plant first and either pull the lights up or do it before lights out. And keep those temps down. Good luck.

 

[bobman]

Btw always test a plant first if u r giving them something new if u are unfamiliar.

 

[Seal-Clubber]

Maybe but I dont think so. In a well buffered soil ph should not be an issue unless u are way off or something crazy happens. Now as far a nute burn maybe but the location and coloration of the marks dont lead me to that conclusion.

over-watering causes "something crazy" to happen. In this case, the soil no longer drained properly and the roots began to stagnate and this is what caused the chelation to change. example : DWC hydro, at 4.5ph, this will happen.

 

[bobman]

Buddy over night does not cause this. This is not dwc. I have done soil and hydro. I stand by what I said. Do not make this more confusing than it has to be.