Vegetables Which Don't Quite Look Like What They Are

I am mostly working on hatching.  I find that I want to make my hatch marks too long.  Overall, I seem to rush, so perhaps I need to add a bit of patients.

Here is a potato, which doesn't look particularly like a potato to me or at least not the potato I was drawing.  The part which is concave is way too large and the top is too rounded.

Here is an onion.  I want to keep practicing to figure out how to build the types of shape and volume that I want.  I hope this will crossover into better paint strokes.