One of Three problems

Ok I am new to growing and have a few plants outside. I didn't check the soil before I planted the plants they are now between 2 and 5.5 feet tall I planted outside in The end of may. Just recently about a week or a little more ago i noticed the leaves were starting to get yellow spots on them. This only happened about a week ago and I'm not sure what it is. I have 3 guesses nitrogen defficiency, possibility of the soil being too acidic, or maybe even root rot(they are near a creek but not too near). Please anyone who knows what each of those problems symptoms are let me know and I'll try and play plant doctor to help my girls out. Thanks!

yea thats been happning to my plants lower leaves.

what kinda nutes are you feeding

N def- intraveinal chlorosis. That mean in between the veins you get yellow shading.
Acidic- Lots of symptoms, can present as deficiencies, or leaves turning burnt and crispy.
Root rot- entire plant wilts and dies.

Have you considered the possiblity that some other creature is consuming your cannabis before you get a chance to? What about thrips? Pics please!