Here, answer as many questions as you can. The more you answer, the more likely we are to diagnose properly:

-indoor or outdoor
-soil, soilless, or hydroponic
-specific medium
-Soil type/brand
-Hydro/aero/soilless system type
-Anything you have added to the soil
-Soil pH
-Water source
-Water pH
-Age of plant
-Type of fertilizer
-Rate of application
-Lighting source and distance from plant
-Temperature (both day and night if you are running a dark period)
-% Relative humidity
-Lighting schedule
-Type of ventilation your room has

Are you in a soil that has a lot of peat in it? I am guessing by just the pics a potassium lockout caused by low pH. But with no other info, that's a rather wild guess at the moment.
stinkyattic Reviewed by stinkyattic on . im new to indoor growing- spots on leaves im starting to get yellow spots on my 3 week old plants not all of them but a few are can someone help me out and tell me whats wrong and what i need to do thank you very much there on a few of the leaves Rating: 5