Blocking people from seeing your Farmville updates?

Answer 1

I don't you can block people from seeing your updates.

If you disallow Farmville to receive notification updates in your application setting, you won't receive any notifications at all. Hence, it won't stop sending notifications or updates of yours to your friends unless they also disallow Farmville to receive notification updates.

I think what you should just do is don't post any updates such as when leveling up or mastering a plant or anything that need to post in your wall.