I do. It's obviously going to depend on your baseline pH -- you don't want to add to much if you are tending to alkaline already. Since my soil is neutral to slightly acidic I don't seem to have a problem. For many potassium-loving crops I'll work wood ash into the row at planting time. It's made a huge difference for my peppers, for example.
That's a lot more than I would have thought. I'd guess I'm using the equivalent of 1/2 a ton per acre at most. Theoretically that should only affect pH sensitive crops like spinach. But on the other hand, if your soil pH is already acidic you may want to use quite a bit.