Sounds like b8, but just in case.
Remember two things:
The Sabbath is one day, not two. You don't get out of working the whole weekend.
The Sabbath is for man, not man for the Sabbath, and your relationship with God should be personal. You need to figure this out for yourself. For some people, yard work is incredibly satisfying and refreshing, especially if you work an office job. For other people, it's like another day of work. If you're the first, do it. If you're the second, do all of your yard work one day so you can take the other weekend day as a Sabbath.