Potassium Deficiency or Excess?


Autumn Haze Autoflower
Indoor Tent
Temperature: about 65- 70 degrees
Humidity: 60%
Ph: ?
LED lights (300W and 1,500W)

I raised the lights as the Sativa has grown higher. It is about 12” above.

A little over a week ago, I added Miracle Gro Organics for Edibles (7-6-9)

edit: unauthorized link

I’m seeing this on the leaves. What should I do?

You say you raised the light to 12”, what were they at before ? Looks like some of your leaves are folding up on the side which could indicate heat stress/ light stress. This could also be why your seeing yellowing, Also seems like most of the damaged is towards the top closest to light.

Miracle grow not the best chose for cannabis, but I have seen successful grows with it.

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They were around 8”-10”, but mostly because they grew faster than I thought. I’m growing a Blueberry as well that is about 2 weeks ahead and is now smaller.

The color on the edge of the leaves, plus some yellowing of other leaves made me think something might be off. I only used a small amount of the Miracle Grow. I didn’t want to introduce too much in terms of nutrients.

I am currently dealing with an issue that I think is a potassium deficiency and i have been using Fox Farm Liquid Nutrient Trio Soil Formula: Big Bloom, Grow Big, Tiger Bloom (Pack of 3-32 oz Bottles) 1 Quart Each. This is a picture of my issue and it is only in the mid to low branches and seems to be mobile. II would just like to make sure that is the issue or if I have over fed. Any and all help will be greatly appreciated!


I’m still pretty new at this. I got two plants to harvest last month. My main problem was trying to do too much. I watered too much, and tried to figure out nutrients too much. Some very good people here advised waiting and seeing. The plants kept growing. The leaves did not look perfect. Water drops on leaves created burn marks where the light was focused. I’m not sure what happened with other leaves. But, as long as I didn’t water too much, and I was a bit minimalist in adding nutrients, they kept growing.

Those leaves look fairly healthy. Maybe be a bit patient and see if there is something actually happening, or if you have a real issue.

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Yes I do believe you are correct! I am however going to defoliate. Any help is greatly appreciated Ty Newgrowr

I identify with this as a noob. Still on my first grow and i’ve found the same, just be minimalistic and don’t change too much too fast (or at all alot of the time). Watering / light height was and is a hard one for me, never entirely sure, but through writing things down and keeping track it gives me an idea of what is a normal amount of water and what isn’t for example.