Wait until the blossom has dropped off and the pear is at its earliest stage of development. Place the bottle over this proto-pear, tie it securely in place, and allow the fruit to mature inside the bottle as normal. This helps to stop the fruit rotting, and directs all the nutrients to the pear growing inside the bottle. It can be cut from the branch when it is mature. Refinements, such as peeling the pear inside the bottle, call for a good set of appropriate tools and a steady hand.
Some Japanese farmers grow melons inside cube-shaped containers.
As they grow they fill the container and end up as cubes. Although edible, these melons lack flavour and are primarily ornamental. The idea of bottling fruit while it is still on the tree has been taken up in California, where they grow aubergines in plastic moulds to make them look like the faces of celebrities such as Elvis and Bill Clinton. Always expect California to go one better.