Re: Moving back to Pakistan . .
Fail !!!
What has that addition to do with the original proverb? I know what you are trying to say but it doesn’t fit …
Grass is greener on the other side means:
Humans are generally ungrateful - we always wish for what we don’t have and when we get it we want something else or want to go back … The metaphor explains the anecdote of why sheep keep jumping over the fence to eat grass on the other side, but when they get there they just jump back spending all their time going back and forth they lose the plot which is to actually get a decent meal …
Now, your addition - but you still have to mow it … makes it sound hilarious 
Sheep don’t use lawn mowers … and the “greener” look is supposed to be an illusion it is not supposed to be a reality … however, you explanation is saying that “hard work” = “mowing” makes the grass “greener” … So are you saying that “hard work” makes the illusion stronger?
catskin - said “munch” she was right - she was thinking of the sheep - for some reason you were thinking of gardeners … LOL