Hi Tractorqueen,
I am sorry I didn't mean that you were not paying enough attention to your dogs. Now I know that your dogs have been attending obedience trainings, etc. then, you can teach them to "Leave it".
One thing I want to point out is though,
You are asking "how to get them to keep them out of mischief" but how can your dogs know the difference between the garden hoses and toy ropes? When they chew garden hoses, you call it "mischief" but from your dogs' point of view, chewing hoses and chewing ropes are the same. Maybe chewing hoses is more fun because they will soon get your attention (scolding=excitment)!
What they need to know is that some specific items are not OK to chew, right? You can train them by either keeping an eye on the moment they are about to chew and tell them to "Leave it" or reprimand each time patiently, or put some bitter tasting object such as tabasco sauce or something on the hose so that the dogs will learn to dislike it. Or, as I said, manage the situation - put the hose away, or supervise the dogs when they are outside.
There is no magic wand so I am afraid you will have to just keep telling them to "leave it" every time you see them getting to the hose, or anything you don't want them to access to.
Maybe someone else has some bright ideas????
