Help, What is wrong with these leaves?

Im growing out doors and im just not to sure what is wrong with some of my plants. Leaves near the bottom and some middle are turning yellow and brown. plz help

The PH is off.. you have to ph your soil.. are you adding nuts?

I am using worm castings and sunshine mix 4 and using biothrive fert which is 4-3-3 and i added some cal mag because i thought mayb it would help but hasnt really

check your soils ph.. that would be the first thing I do.. if its too high it would effect the nutrient uptake.. (thats my thought)

always check ph first and it looks like theres a few problems there.

Ok thanks I can just use litmus paper to tell ?

Isn't litmus paper the same as the strips for reading pH? You can use anything to check pH. Should always check pH of the water you're putting in as well as the run off that pours out from underneath. I do not recommend using the Electronic Soil PH Meters, they aren't worth the scrap its made with.

Well all of my og kush seem to be fine just some if my sour kush so I think the water is fine but I will also test that then

Would my fertilizer of made my ph change then if the water is fine?

I don't know about ALL ferts but I know for sure that the Fox Farm nutes/fert I use do cause the pH to go down. I've been told my a hydro store that "depending on what you're growing" (they always say that since its illegal to grow in my state), that plants will generally change the pH themselves as they grow as well. So even if it isn't your nutes or fertilizer that is causing the pH fluctuation, the soil might start getting concentrations of certain things that will also change the pH. So it can be a number of things which is why it is always a good idea to check the pH of water going in or out.

I don't know about ALL ferts but I know for sure that the Fox Farm nutes/fert I use do cause the pH to go down. I've been told my a hydro store that "depending on what you're growing" (they always say that since its illegal to grow in my state), that plants will generally change the pH themselves as they grow. So even if it isn't your nutes or fertilizer that is causing the pH fluctuation, the soil might start getting concentrations of certain things that will also change the pH. So it can be a number of things which is why it is always a good idea to check the pH of water going in AND out.

Ok sounds good I will check my ph's in the next day or two ,thanks!

So I did some reading and found out bio thrive Has a ph of 4.6 . Would it help if I sprinkled garden lime on the top of my soil? Because I have some lying around. And I will get my ph tester if the store is open today(Sunday)

Petstores have fresh water pH testers as well. Lime is good for stabilizing but I am not sure for applications after planting. I know you can do it just don't know how much to put or whether to add to soil or water.

If your PH was off your leaves would start to turn yellow because having a close to neutral ph is what allows cannabis to uptake nutrients. Your leaves look like they are being over fed because of the burn that is present on your leaves. If it were my garden i would cut out plant food and give fresh clean water for the next few waterings. And when they start to bounce back and you decide to feed again, cut back to about half the amount you were using to begin with. Then if they take that amount well and you feel they could use a stronger feeding, then increase accordingly but do so slowly. space out your feedings and you shouldn't see this type of burn again. Good luck and much respect