How do I start my square foot vegetable garden?

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Question by NamNam: How do I start my square foot vegetable garden?
I’m starting a square foot garden, and am planning on growing lettuce, tomatos, strawberries, peppers, beans, maybe carrots, and cucumber. I’ve NEVER had a garden before, and I need to know EVERYTHING. What should I do about soil? I’m building 3 boxes (more like frames) that I’ll be putting in the yard over really stoney ground. But I’m planning on filling the boxes with soil (if this makes any sense) so I need to know:

what type of soil I should use,
when should I start planting,
how should I plant them? I’ve heard of starting the plants in pots inside, then moving them to the garden when they’re a bit larger. Or is it better to grow them right in the garden bed?

I’m planning on growing tomatos, do I need a pole or something for them to grow on, or do they grow on the ground?

And any personal tips that you have would be amazing also! Thanks in advance, and sorry if the question seemed scattered.

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