Anyone know what these dark spots are?
- Thread starter oill
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Hugo Phurst
Well-Known Member
Nute burn?
myke
Well-Known Member
Or nute lock out from build up?
hotrodharley
Well-Known Member
Light type and distance from the top of the plant?
You didn't read properly, because lack of N does not cause leaf spotting, and the yellowing it does cause, starts at the very bottom of the plant and moves up. Not to mention the OP clearly states he grows in hydro..so coco assumption was also misread, or unread.
Not having experience in hydro, i can't really say how to fix it, but the plant is showing signs of possibly a calcium deficiency along with some magnesium. The spots may also be caused by a lack of manganese, which can happen in hydro if ph is kept a bit too high for too long. 6.0, if that's constant, may be a bit high. What are you using as your nutes? Do you have a pic of the plant from say 1-2 weeks ago?
No idea what yls is...but i'd love to see an ARTICLE where it states that lack of nitrogen causes yellow spotting near the top of the plant! lol
CannaCountry
Well-Known Member
I agree with Blitz35; looks short on Mg and Ca. Be careful trying to fix this at this point in the game.
You didn't specify your medium, if any, but you do mention that you're growing in a hydro set up of some sort. I can't comment on any form of hydro except for a setup using coco as the medium and in that case, the 6.0 pH is a little too high. I would hover closer to 5.8 if this is the case.
Good luck.
You didn't specify your medium, if any, but you do mention that you're growing in a hydro set up of some sort. I can't comment on any form of hydro except for a setup using coco as the medium and in that case, the 6.0 pH is a little too high. I would hover closer to 5.8 if this is the case.
Good luck.
3rd Monkey
Well-Known Member
With Blitz and CannaCountry (how in the hell do you like posts here).
Definitely seems to be ph or your EC has risen and locked it out. Whats your res say?
Definitely seems to be ph or your EC has risen and locked it out. Whats your res say?
Led. Using cob at about 2 foot away. Temps are about 25c. (need higher temps w cobs)
Using the tiny rockwool chunks
My run off is mixed with the dehumidifier run off so hard to tell.
I think potentially there has y been enough run off so it's salt buildup
Rockwool mini chunks... I start at 5.8 and then usually raise it to 6 later in flower for better pk uptake.
3rd Monkey
Well-Known Member
Just reread the OP. 1.8 EC?
That seems like so little. Doesn't look like you've tried to push feed heavier either.
By week 6 I would think you'd be over 2 pushing 2.5.
Perhaps I'm wrong, but now that I look again, looks like they are hungry. Potassium specifically.
Without seeing the rest of the grow or before the onset, it's hard to tell.
3rd Monkey
Well-Known Member
Have the leaves always been so light with dark spines?
Thanks for reply. I'm using bcuzz hydro. Rockwool mini chunks is the medium. I usually raise it to 6 as the grow moves to flower.
I now think that the volume of water wasn't enough to get run off. I think it's salt build up. So I have increase the feed time.
Yes.. Since a Cold snap a few weeks back
Last round I never went over 2ec. I wouldn't go over 2 in an led grow without co2.
I defo think I under fed them the week before this but looking at weekly ec charts on Google images most of them say about 1.8 in week 6. Moving up to 1.9-2 tomorrow.
Again I think the issue has been that this plant didn't get enough water to achieve run off. Have upped the dosage... And this shoukd help.
3rd Monkey
Well-Known Member
Yea, you know your plants better than anybody so I'm sure you'll get it dialed in. Good luck and update if you can. I'd like to know what it was for sure.