Pick the mint leaves and reserve the stalks. Score the vanilla pod lengthways and scrape out the seeds, reserving the pod.
Put the sugar and mint stalks in a small saucepan with 200ml water and bring to the boil. Turn the heat off, then add the zest and juice of the limes, and the vanilla pod and seeds. Mix it all together and place to one side to cool down. You want a lovely thick syrup, but remember it will thicken as it cools.
Wash the fruit gently in cold water and drain in a colander. Halve and stone the cherries and chop any larger berries in half, then spread them out on a wide, flat dish. Halve and stone the peaches and apricots, then cut them into nice wedges and put with the berries.
Halve the melon, scoop out the seeds and chuck them away. With the same spoon, over the dish of fruit, scoop out curls of melon until you reach the green skin. Pour half of the syrup over the fruit, cover and chill for a while, so it soaks up all that lovely flavour.
To serve, pick out the mint stalks, then sprinkle over the mint leaves. Serve with dollops of natural yoghurt if you like, and a little jug of your leftover syrup for drizzling over.