Grow light Wattage requiements for three seedlings in 5x3 space

Wattage measures your electric bill. You want par value. 5x3 in flower is different than in veg—- that’s why grows have different lights—- or areas. Get a broad spectrum light and if I had the money, the gavita 1700e would be my choice. But I just use mars hydros—- if you bought 4 you should be fine

Heya! If using quantum boards 450-500W would light that up nicely! With QB's a good reference is 30-35W/sqft or if using blurples a little higher at 50W/sqft. During the flower stage the plant absorbs a lot more red light where as they absorb more blue light during the vegetative state. I would recommend using a board that is white LED's opposed to just red and blue. If you go that route the best white spectrum for a full cycle light would be 3000k-3500k. The manufacturers will also list heights typically for different stages of growth. Good luck with your venture!