Step 2 – let them eat it.
That’s kind of it, really. After two years with an allotment (and three with a child) we’ve found this to be far and away the most effective approach. This morning The Boy has gorged himself on his own bodyweight of organic raspberries and strawberries, fresh off the bush via his own (grubby) hand.
You can even make use of them to water things, carry weeds away and drown slugs, but first you need to get them interested 🙂