Help! Yellowing spreading laterally. Week 7. Indoor soil

[Inf3cted]

>> LOL! I tried to warn you, that soil probe was not to be trusted,... you might have over done the acidifying too,... what was the pH before watering? ...recall, RO/DI water has no buffering capacity, so small input can result in big swings, and any solution made from it, even if adjusted again, will not stay stable,... buffering is a self-correcting action that involves the chemistry between carbonates and H+, and there has to be enough of them in there to be effective...

yeah man that probe has been reading 8 for a while now. It must be broken aye.

Thanks for the tip on RO water properties.

How are you testing your run-off, mate, I forget... a meter? Is it calibrated recently using a dedicated soln. for this?....

Yes digital pH pen type meter. I will be calibrating for the next session once again.

IF those pH reading are accurate, then for sure pH is too low,... you need to add a Ca-Mg product derived from carbonates, and/or dechlorinated tap water that has mineral in it naturally,... Flushing with slightly elevated pH water will help correct, but as you flush, nutrients get washed out as well,..

Pretty sure I nailed this down and it's obvious now why the condition hadn't improved since almost 2 weeks.

It's hard to find a calmag product for soil. I was trying to keep it natural/organic but if I have to I will buy the individual elements for cal and mag and mix them in.

I do have black molasses and dolomite (liquid) and lime(liquid) on hand but those are more conditioners than dedicated cal/mag products.

this is why the final pour should have Ca-Mg and very dilute nute's in it,..

Yes the last 1.5litres was a split between dolomite and kelp for conditioning the soil and dilute nute with ratio of 10% 2% 9% npk

Some others have called the color loss right too-- I see definite N defc. happening now (not S- that affects top growth first), but not from lock-out...Mg will be restricted at this pH, but not N.... N has a very robust availability across a wide pH range,...Mg defc. show typically with green veins, and yellowing in between, sometimes with edge/tip necrosis; N defc. shows color fade veins and all, seldom with necrosis until maybe the very end (before it drops off) if at all,...

hopefully the flush washed off the roots well and the mild feed makes it way to refuel these girls. Here's some more pics of different leaves, looks like you are right yet again on the N deficiency as well as Mg.

Green veins on a few leaves. The total yellowing is more common than this
View attachment 427248

Slow spread to the top
View attachment 427250

In flowering, N doesn't get top billing, but N is needed all the time regardless,... it just shouldn't be the largest # in the NPK %'s,.. we see N starved plants in bloom often, and the bloom nutes may not have enough for demand,... It's fine to mix in some grow nutes with your bloom to up the N some, just don't switch back fully to grow nute's to treat,... how much grow nute's you will depend on what the NPK numbers are in both grow and bloom nutes,.... for example, say I have 10-5-8 grow, 5-15-14 bloom,.... here, and even blend of both would be fine, but make sure your total dilution is the same as usual,...if you're feeding at half strength for example, don't add half strength doses of both combined, add 1/4 strength of each for a combined half strength,...

That makes perfect sense.

That soil will be a source of crap until the end I'm afraid,... there's really no delaying of blooming, or extending it after the fact with auto's,... forcing usually just ruins yields and causes hemi' behavior,...

Yeah I definitely understand the need for controlled mediums for autoflower. So used to the outdoor game in soil that but lesrning quickly that indoors is less forgiving due to timeframes and all about accuracy and consistency!

As for the flushing, run the pot's equivalent volume through first, then retest,... the less drowning of the poor thing you do, the better!.. you saw the fast drainage tips at LHT already, right?
... before the next grow, if you have the cash to spare, get that Accurate 8 soil Probe, and a TDS meter to see how hard-- and therefore, well buffered-- your water is before you do any tweaking,... :smoke:

Yes I ran about container size/vol for the flush with the last litre mixed with dilute amendments.

I will invest in the A8 for sure. Also considering coco.

Peace and Respect for your help my friend

 

[Inf3cted]

I think I see a difference.... Or atleast it hasn't spread any further and it doesn't feel like the colours are screaming at me.



Waira mentioned tip burn necrosis for Mg deficiency. Is the below pic an example of deficiency or nute burn(how?) or heat stress ? Had some crazy temps here last 10 days.



Thanks everyone I feel a bit more relieved

 

[Waira]

pardon the delay, mate! ...General Organics CaMg+ is what I use, made from dolomite and plant extracts-- good stuff! ..***... look up the coco experts here- Bromeo, Gcase, Blue too I think,.. seems this is a higher labor medium to use, lots of do's and dont's, more so than soil,...research carefully before you take this on....
... halting is a good sign! ...some reversal is even better, though it's often rather limited,... that tip yellowing/necrosis is nute burn symptom,... Mg defc. usually doesn't show spotting and tip/edge necrosis until well advanced,... Hang tight bud, you're almost there!