Cat owners--I need advice!!!

[mondaymornin1]

I'm having major troubles with my 2 kitties crapping in my flower garden! What can I do to keep em' out of it? Since the weather is warm here now, they've officially become "outdoor kitties." We have 4 friggin' acres for them to crap on, and they chose the nice garden I worked hours in! It smells worse than their litter box, I swear. I put a huge pile of old sand at the woodline behind our fenced-in yard. I guess it's just too far for the little divas to walk. And I tried putting mothballs in there--blech!! That doesn't smell much better, and it's too close to the house.

Any suggestions, cat people?