Personally, I wouldn't depend on the contents of that Dr. Earth Veggie & Herb fertilizer, even tho I've read up on it and there's a lot of good stuff in there. In my judgment, it may not be enough.
In your situation, I'd fertilize once a week with (1) liquid seaweed and (2) a good quality liquid fish fertilizer. That'll probably be enough. Best of luck. What are you wanting to grow in your 4 X 4, anyway? That might help us give you better advice. Some crops want more nitrogen and others less.
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