My go-to favorite is ruby swiss chard; very hardy, and you can cut the outer leaves to keep it coming. Saute in olive oil with fresh herbs and pine nuts (I add diced ham, too) - yum! Lynn

How high are the timbers/bed now? You could just replace them with fresh timbers. I had to move my 8'x4'x12" raised veggie bed this spring. I pried the frame up, moved it to where it needed to be, and then shoveled the soil back into it. Point being, the soil mostly stayed where it was after I lifted the bed frame up, with just a bit trickling down on the sides. You'd probably find the same situation: you remove the rotting timbers, the soil mostly stays put, you lay down and secure new timbers, and perhaps you have to do a bit of cleanup shoveling. If you don't want to use timbers, you might be able to use boulders/rocks, depending on how high the sides of your bed are. All of my perennial beds are edged with boulders, ranging in size from about 6" to 12" in diameter. It takes a while to figure out which stones need to go next to which other stones for the best fit, but I like the look of the end result. It's not as easy to weed-whack between the stones, however. I usually just end up hand weeding while I'm tending to the rest of the beds. Timbers are probably cheaper, unless you have a place where you can get cheap stone. I dug most of my boulders out of my yard, and bought the rest at a local hardscape supply yard for $35 a wheelbarrow-load.

Our garden in Northern CA needs new soil after a dismal few veggies last year. How and what do we add now in the winter for spring growing of tomatoes, onions, squash, cucumbers and herbs?

The whole New England area, but especially ME, VT, and NH, look best with stonework, which is so natural and abundant in the area. Fabricated stone or blocks just look out of place. But, stone costs a FORTUNE. Even though they often get it just down the road, it's expensive and the labor for a TRUE stone mason who knows how to place them can be significant. Do not let just anybody put stone up. The dirt behind the stone wall will be exerting pressure, and somebody who doesn't know how to build so it is truly stabilized will leave you with a wall that will last many years, but not enough. After ten years, sometimes much less if the work was bad enough, the wall will start to lean forward. That's a long way of saying one thing--if stonework is out of the budget, I'd really explore the suggestions here to get rid of the terracing and grade to a slope, and it looks like the slope would not be steep and unworkable.