new raised garden beds
I just bought my first house and it has a large yard with a garden plot (about 8'x12'). Within two weeks I had a large yard and weed plot (about 2' high weeds).
I fought back and the weeds are now residing in the bottom of my new compost bin.
Ok, on to the real topic. Rather than use the ground-level existing 8x12 plot to grow vegetables, I think I should probably do a raised garden plot for two reasons: 1) I have a 9 month old puppy who thinks that a large plot of dirt is great fun. Raising it, even a little, should make it easier to convince her that it's off-limits. And 2) this should increase drainage and let me set up a lasagna garden.
Is this correct? Is raised better than ground level? If raised is better, how high should I make the walls?
My next question is that, if raised is better, what should I use for sides? I was thinking that a small wall of piled slate would be attractive and allow for good drainage. However, this would be more expensive and use up a good deal more room (see thrid question below). All the pictures I've seen on this site use wood, but I'm concerned with appearance and durability.
Lastly, should I stick to a single plot or should I break this up into multiple 4x8 rectangles or 4x4 squares, ala square foot gardening? If I'm making slate walls, this could use up a lot of room.
What have you had success with? Pros and cons of each?