Name this deficiency.

Cousin Bo

Well-Known Member
Any ideas. Soil with dry amendments. I had K deficiency in some other plants from what I think was too much Mg but this one looks different. The other plants just had yellow leaf edges but this one has blotchy spots that have been getting progressively worse. It's not a huge deal since they're about done but I want to know what it is.

yellowspots.jpg
 

bignugs68

Active Member
Nubcake here. I agree looks like potassium, BUT! I wonder about Calcium toxicity since some of those fan leaves are yellowed more at the center rather than working in from the tips/edges.
yellowspots~2.jpg
how-to-find-and-fix-nutrient-deficiencies-and-toxicities-in-cannabis-plants-165453_870x420@2x.jpg
 

Cousin Bo

Well-Known Member
Nubcake here. I agree looks like potassium, BUT! I wonder about Calcium toxicity since some of those fan leaves are yellowed more at the center rather than working in from the tips/edges.
View attachment 5375142
View attachment 5375144
I was thinking maybe Ca deficiency but I see pics that look identical some sites say is K deficiency and some say Ca. Grow Weed Easy says it's Ca but I don't really trust them a whole lot.
 

bignugs68

Active Member
I was thinking maybe Ca deficiency but I see pics that look identical some sites say is K deficiency and some say Ca. Grow Weed Easy says it's Ca but I don't really trust them a whole lot.
I hear ya bub. Based purely on pics and quick tips I've read, I don't think Ca deficiency. it's spotting and such usually stays between veins, yours is blotching regardless of vein lines.

Another quick tip graph that's looks EXACTLY like your leaves -
calcium-excess-in-a-cannabis-plant.jpg

Do you use Big Bloom?? I know my plants in week 4 veg were quirking out on me(some orange spotting in fan leaves, edges that's were yellow/orange like powdered cheese flavoring for popcorn.Big Bloom added stability and within 2 days growth resumed.
 
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Cousin Bo

Well-Known Member
I hear ya bub. Based purely on pics and quick tips I've read, I don't think Ca deficiency. it's spotting and such usually stays between veins, yours is blotching regardless of vein lines.

Another quick tip graph that's looks EXACTLY like your leaves -
View attachment 5375175

Do you use Big Bloom?? I know my plants in week 4 veg were quirking out on me(some orange spotting in fan leaves, edges that's were yellow/orange like powdered cheese flavoring for popcorn.Big Bloom added stability and within 2 days growth resumed.
I know what you mean. All the pics I've seen for Ca deficiency have been the brown spotting. That pic from Grow Weed Easy was the first I've seen that look different. But that picture says that's the symptom when it happens during flower which is when mine started. I just think I'd see K and Mg deficiency symptoms if there was too much Ca. I'm not sure.

It's soil with dry amendments. It started after I top dressed with a mix that was 1/8 langbeinite and 1/8 kelp meal so I think that was too much Mg. It also seemed like it might've gotten a little worse after I added some potassium sulfate but don't know if that made any difference or not.
 
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