-
ICMag with help from Landrace Warden and The Vault is running a NEW contest in November! You can check it here. Prizes are seeds & forum premium access. Come join in!
Mysterious deficiency
- Thread starter cidA
- Start date
goingrey
Well-known member
Check out this guide from Dutch Passion, it's the best one I've come across: https://dutch-passion.com/en/blog/a-visual-guide-to-cannabis-deficiencies-n987
According to it...
Yellow at the top of the plant and green at the bottom? That would not indicate an iron deficiency.
Yellow at the edges of the leaves/fingers and green in the middle? That would not indicate a sulfur deficiency.
pH sounds ok for coco.
Light bleaching, maybe.. Is the light really close?
Or Koondense could be right. Although the leaf tips are burnt from too much nitrogen so I dunno. But maybe that's from a while ago already?
According to it...
Yellow at the top of the plant and green at the bottom? That would not indicate an iron deficiency.
Yellow at the edges of the leaves/fingers and green in the middle? That would not indicate a sulfur deficiency.
pH sounds ok for coco.
Light bleaching, maybe.. Is the light really close?
Or Koondense could be right. Although the leaf tips are burnt from too much nitrogen so I dunno. But maybe that's from a while ago already?
goingrey
Well-known member
Doesn't sound like it's the EC either then?
jackspratt61
Active member
What type lighting?
What ppm n-p-k-ca-mg-s?
How far along are they?
Can you get a whole plant pic?
What ppm n-p-k-ca-mg-s?
How far along are they?
Can you get a whole plant pic?
I would need more information. What nutrients are used? What is the pot size and strain? Also more photos of the whole plant would be helpful.
Just for clarification, do you mean your final EC is 1.5-1.8, or 2-2.3?
Looks like they need CalNit and Mg. Do you have an EC measure for the runoff?
i agree with troutman acidic ph spiking the ec locking out potassium leading to mg deficiency. make a batch of feed at 1.0 total ec and 6 ph. runoff to 20% and check runoff numbers. compare those to 1.0/6.0 feed. im guessing the runoff ec will be in the 3.0 range. low ph is killer while high doesnt hurt til 6.8/7. pulling light away while recovering is a great idea too to lower transpiration while the rootzone is compromised
If you are using a complete fertilizer it wouldn't be a deficiency. If you have signs of a deficiency when using a complete fertilizer then it's a pH issue. When you use tap water your pH will rise in the root zone and lockout nutrients due to the receptor's sites getting blocked. The major nutrients are there but not available because of the hydroxyl content in the root zone. (alkalinity). If you use pure water and fertilize together your pH would be more manageable. When people try to add individual nutrients like iron or sulfur to fix a problem they only make it worse. 
