AF COB soil problem calmag ?

[drnkenmnky]

Hello AF community!
I started a new grow with autoflowers.
They started very good but after a while they start showing strange signs.
Droopyness .. marks on the leaves and those leaves die after a while.
I always PH the water so that shouldn't be the case.
Soil is 5-6.5 bought in the store. ( added some blood flour and bone meal )
No additional nutrients.

Lights are 350W Cobs and 125w quantum board
Only water them after my sensors say the ground is dry
RH goes from 40-60 ( depending on waterings)
I don't water them alot
But previous times i had some problems after to much waterings so thats why i try to not give them too much now..( maybe too less now )
They all got the same history and some are really dark green without alot of those signs while others show way more..

 

[Animatey]

I dunno much about soil but those gals seem to be deficient in a few nutes and probably just need to be fed more. They are light green which is sign of N def, and yellow between veins which is sign of Mg def and the brown spots look like maybe Ca def...

I dunno how to fix this in soil but you could post what you have been feeding them and how often and then other soil growers might be able to help easier. Good luck bro!

 

[drnkenmnky]

Thanks !
I have them been feeding nothing..
The bone and blood meal where only from the start in the ground. There is also perlite and lava rocks in it the soil for more oxygen.
Temperature is 22-28
Air flow is good
Extra ventilator also inside
Only the air is not fresh.. i try to open the door sometimes but its in a moldy room underneath the ground. I use a dehumidifier though.
Next time ill use proper soil again with magnesium and calcium already inside. Also the genetics arent really my thing. They are very small. I bought a bunch off chaze super for the next rounds.

 

[Animatey]

Thanks !
I have them been feeding nothing..
The bone and blood meal where only from the start in the ground. There is also perlite and lava rocks in it the soil for more oxygen.
Temperature is 22-28
Air flow is good
Extra ventilator also inside
Only the air is not fresh.. i try to open the door sometimes but its in a moldy room underneath the ground. I use a dehumidifier though.
Next time ill use proper soil again with magnesium and calcium already inside. Also the genetics arent really my thing. They are very small. I bought a bunch off chaze super for the next rounds.

I think you need to feed them... I'm not sure but i think it takes more than bone and blood meal to make a soil that can feed a plant when only providing water.

I think one of these guys would know:
@Arthur @Waira

Do you have any bottled nutrients?

 

[Arthur]

Looks underfed, with a cal/mg deficiency on top.

You can't trust what a shop tells you the pH is of a soil anymore, qc seems to be in the back toking...check for yourself. Plus, you changed the pH by mixing in blood flour & bone meal.

Check the pH of the soil first, then, get some food to those girls. Under LED, cal/mg is a must. I have several strains that want it at double the dose recommended.

 

[Waira]

-- lots going wrong here sadly,...
- what soil is this? If the label said 5.0- 6.5, that's plain alarming... 5.0 is disaster -inducing pH, nearly 1.5 off the optimal... remember, pH is a logarithmic scale, each jump of 1.0 is in fact a 10x/decrease.... decimals matter, is the point!
-- blood/bone meal are slow release, and depending on the base soil's richness, lacking in several other nutrients,... things are way out of balance now..
-- in-pot pH is a must to monitor, otherwise you're just rolling the dice,.. If that goes off, certain nute availability follows in kind....
>> this plant looks multiple nute starved, so much so I can't tell what's cause and what's effect,.. lack of certain ones, inhibit the uptake and processing of others, so things can snowball very fast in such a case,....
pH confirmation and correction is critical now,.. adding more nutes blindly may make matters worse, not better... I figure the hang up is you don't have a soil pH probe handy, (forget the cheapo skinny ones, they're lousy)... Accurate 8 is a good unit for the money,....
Watering enough to keep a consistently evenly moist soil is important too, big swings in wet/dry are not good at all,... several physiology, pH and ppm things linked to that which I won't go into here.... .... let's just say the roots dislike it, and it messes with efficient functioning,....
So, what to do,... since no pH reading is available anytime soon, last resort is a crude run-off test using only RO/Di water so as to not skew the readings with water that has any form of pH buffering, which is what minerals (mainly CaCO3) do,.... Water to get about 25% run-off, collect the last bit on final pour (clean cup), early stuff is way loaded with dissolved stuff and less accurate.... Make sure your pH meter is calibrated, and if you have a TDS/EC meter, that may offer insight as well,...
Getting feeds in ASAP is key now to save her,... feeding w/o doing a ph test is a risk, yours to take or not,.....

 

[drnkenmnky]

Okay So ph of my soil was around 6.5
I tested it with destilled water + the soil and my PH meter.
This should be good right.

And i always ph my water before giving water because its around 7-7.5 here.

I've been looking to my other soil i used in the past, so much better.
It already had perlite in it, and had nutrients for 1y in it + calcium & magnesium in it..


Shouldn't have taken the cheap ones.

Thing is, i have some plants that really don't show those signs..
That still are dark green and only bit droopy or not at all droopy. ( but no yellowingz)

And they all got the same soil or water or light.


I have NPK 13/14 or autoflower supermix in here but no CALMAG.
I'll try to get that before next watering also.

BTW our tapwater has a high PPM( (yes i have a meter)
So thats why i rather stay slow on the feeding..
I also have a RO thing but its a bit a hassle to less it drip the whole time(no good place anymore for it)

Thanks all

 

[Arthur]

You could rotate everyone and see if its environmental pretty quick...

 

[Arthur]

What's in the water....
My tap is around 330, but the majority is salts... not good. I run RO for the grow and drinking water.

 

[Tom Bombadil]

feed it.