GrowCNanswered grow question 3 years ago Yes, they will need feeding. I usually start around week 3-4 when growing in Fox Farm Ocean Forest soil. Other, less nutrient soils may need additional nutrients sooner while others like super soils or living soil could go longer or might never need additional. Visit this website (https://www.growweedeasy.com/cannabis-symptoms-pictures). It lists the most common problems including nutrient deficiencies. With it you can spot nutrient problems to know when you need to add nutes. I recommend keeping a bottle of cal/mag on hand as that's a pretty common deficiency that might show up in a couple weeks for you.
Your pot looks really small. The smallest pot I have grown an auto is 3 gallon (11 L) but I got better yield with 5 gallon (19 L) pots. If you intend to transplant I would do it as soon as possible. I always start auto's in their forever pot so I never transplant. Because auto's are on a fixed schedule transplant shock can affect yield.