Yellow and gray leafs

[Teva]

Hey

First timer here....any idea why this is happening? I checked the tutorials, but none of the images look like this or I'm not seeing it yet. They are 3 weeks old

Advice would be appreciated

Tnx
Teva

 

[SoOrbudgal]

While " checked the tutorials" check for what MJ needs in soil cause your playing right now in poor soil.