The area around Yamunotri Dham is a good belt for apple cultivation. While people living in cities rarely find fruit trees, staying at Janki Chatti while visiting Yamunotri Dham can get them to different apple orchards.
You can take a tour of Apple Orchard and witness how this delicious fruit is cultivated. The orchard owners would love to give a tour and provide the information. If you are lucky, you may get the chance to pick your apple from the tree and enjoy it.