Easier-said-than-done when you have a kid (or two) in your arms while you are cooking, eating, washing up.... The dishwasher can be a blessing for those tools that get forgotten in the chaos of a busy home.
The key is to clean it as soon as you finish using it so theres no time for dried on crud to accumulate.
I almost always peel cucmumbers with a knife - usually I cut a segment and go around in a circle. It comes off like a charm. I do the same for zucchini.