I've noticed that sunchokes are often bumpy. Does anyone know why sunchokes are bumpy? Do they fuse together, or do they just grow like that?
There are supposedly varieties that are somewhat smoother than the standard / common variety. I have not personally grown those, so I don't know if there's any truth to that claim. If I opt to put a patch in somewhere [somewhere well away from any other garden, where they can be mown to control as needed), I'll probably seek some of those out, in the hopes that there is some truth to the claims.
Tuscorara #1 appears to be one such from the few with images at SSE site below. Fuseau is also mentioned as a supposedly smoother one, but no pictures there.
It's the nature of the beast, they are known to be a lumpy bumpy vegetable, fiddly to peel and prepare. Not very nice to eat either, though that's obviously personal to me - we always had trouble using them up, no one liked them much, we used to cover them with cheese sauce and serve as a starter before meals. Pretty healthy though, full of inulin.