Help! Leaves are turning yellow and dimples are forming. WHY!!!?

[TooFunky]

I'm new to growing and have noticed that my leaves are turning yellow/brown and in the worst case my autoflower, some leaves have almost died. Why is this happening and how can i fix it? Any help and suggestions are much appreciated.
Thank You

 

[Jimmycricket]

Re: HELP!!! Leaves are turning yellow and dimples are forming. WHY!!!?

more nutes! multiple deficiencies spotted.

 

[Fuzzy Duck]

Re: HELP!!! Leaves are turning yellow and dimples are forming. WHY!!!?

Most likely k - potassium def on the first pic... not totally sure about the last couple of pic's but might be a micro nutrient def possible Fe - Iron def

Here's a link worth having a browse at - Some plant deficiencies


I would more than likely check growing medium PH value also to make sure that is in the suitable range for growing...