Fert burn or K deficiency?

[Dorje113]

Sure wish you folks that offer advise would give the correct advise.
6.3 to 6.8 ph for peat-based mixes. Keeping it below the low range and you will lock-out nutrients.

Didn't see it was Sunshine Mix, just saw soilless. My Bad. Rusty is right as far as the pH range. Kinda confusing having 2 places where you list the medium though...

edit... make that THREE places :wtf:

[khyberkitsune]

"Only thing that beat's it is growing outdoors. And then...just barely."

Which is why my puny 50w LED panel caused light bleaching on my plants, though I'm only putting 1/3 the power per square foot the sun will do through the atmosphere at sea level?

I think I'll stick with my LED panels when they can put out enough pure power to bleach plants under ~75-80 degree temps.

[Rusty Trichome]

About two months ago, I was given the privilege to see/feel/toutch/taste and smoke LED grown cannabis. The grower isn't a newbie, and has a pretty firm grasp on his equipment, nutrients and genetics. Twas good smoke, tasty and stony.

I'm not at all knocking LED lighting as a growing trend with potential, but my major issue is it's yield. It's nowhere near the yield with HIDs and it's still in the experiment and testing phase of it's development. Speaking of which, if it's damaging your ladies, you might want to re-think your position, lol.

I stand by my assesment.

So Anomander...what do you think?

[khyberkitsune]

"It's nowhere near the yield with HIDs and it's still in the experiment and testing phase of it's development."

I've seen other grows where custom-built LED panels smashed any HID grow (besides vertical.) We're pretty much at LED smashing HID for yield from wheat crops to cannabis crops.

"Speaking of which, if it's damaging your ladies, you might want to re-think your position, lol."

More like rethink the actual positioning of my panels, I'd suppose 50w causing burn from 2 inches, 120w causing burn from 9 inches.

[Rusty Trichome]

I've seen other grows where custom-built LED panels smashed any HID grow (besides vertical.) We're pretty much at LED smashing HID for yield from wheat crops to cannabis crops.

Perhaps with links and documentation I'd acquiesce, but it does sound a lot like the arguments when CFL's were first gaining in pouplarity. However, they were/are an affordable risk.
As I said, I'm hopeful about future generations in the LED realm, but you make my point for me. "Pretty much" there isn"t "there". Once LED's get "there" and the price goes down, perhaps I'll give it a whirl. Until then, on my budget...out of the question.

Seems we've taken over the thread. Oops. <sorry>

[AnomanderRake]

So Anomander...what do you think?

Well...
I am a n00b in all this, but inspired by Rusty CFL talk I am building a clone + mother mini-grow only with CFL lights. Let's see how it goes... :rasta:
But I confess LED seems very promissing!

About my girls, I can tell the problem is gone now. All the new leaves are growing without burns but the old ones didn't recover.
It is still a mistery what happened and I don't now if I actually fixed (and how) or if the problem went away.

The only two things that I did was:
1- Stopped using mineral water (changed to tap with 48h rest)
2- Start balancing the solutions to PH 6.0, instead of 6.5/7.0 like before.

One thing about my soil mix that I think you guys maybe missed is that I'm using 50% of perlite with it. Doesn't this make it work more like hydro? Without nutrients? Maybe thats why the slight lower PH worked better?

Thanks again guys! :smokin:

[Rusty Trichome]

The only two things that I did was:
1- Stopped using mineral water (changed to tap with 48h rest)
2- Start balancing the solutions to PH 6.0, instead of 6.5/7.0 like before.

So do you still feed with every watering? How much and how often?
Ditching the mineral water is a good idea. Too many minerals and metals. Did you know some contain uranium...?

One thing about my soil mix that I think you guys maybe missed is that I'm using 50% of perlite with it. Doesn't this make it work more like hydro?

Why, are you watering them like they're hydro?
No, I didn't miss the perlite. And nope, it's not anything like hydro. And I suggest you keep your ph in recommended range, or you will risk nutrient lockout. How are you testing your ingoing water and solutions?
How are you testing runoff ph?

[AnomanderRake]

So do you still feed with every watering? How much and how often?

Right now I'm feeding 2/1 (two with Biogrow, one without).
But probably because of the high humidity (?) I only water/feed them every 4 days avrg... So since I created the topic I fed them twice and tommorrow is the first one without fert.

No, I didn't miss the perlite. And nope, it's not anything like hydro. And I suggest you keep your ph in recommended range, or you will risk nutrient lockout.

How are you testing your ingoing water and solutions?
How are you testing runoff ph?

I'm testing the ingoing and runnof with a digital PH tester... When the problem started the PH was 6.7 average. Now it´s 6.2 for one and 6.1 for the other.

The burned borders stopped for the new leaves but some of them have the very tip burned, but not spreading to the whole leave.