Its been two weeks since surgery and my doctor has cleared me for cardio (no restrictions) but has deferred weights/swimming until 4 weeks after surgery. I have been walking and riding a stationary bike on a daily basis, and I am looking for some additional exercise options not involving weights or swimming for the next few weeks. For example, do you think a rowing machine would be ok?

Elliptical would probably be better. Rowing is going to engage your core.

Agree. No rowing just yet.

I will hold off on the rowing for two more weeks. My dog is pretty happy with all the walks these days.