Rows? I never count rows. I just knit till it's long enough. The pattern says with 350 yds of worsted weight yarn you'll get appx. 55inches. I'd probably make it longer.. maybe 60 - 70 inches, but you need to buy at about 400 yds and just start knitting.
Cables are easy, but can be time consuming especially with so many of them so keep that mind if this is a gift with a time you need to have it done by.