seaweed isnt a plant food in the compleat sense, it has some nutrients in it but you cant use it for growing, theres little nitrogen in it. its good for trace nutrients to stop deficancies
whats the NPK on the veg stuff?
What are you aiming for?
Best way to treat a weed plant qua food is like a tomato plant.
Are you trying to be organic?
Or just keep your £££ in your back pocket?
use the veg one to grow