Do paths make a difference?
Paths, flowers, and anything else that a character can easily walk through does not make a difference. Trees have to have be 1 square away on all sides from the following to grow: Other trees, bamboo, rocks, buildings, cliff-side, walls, train tracks, river, and ponds.
Also keep in mind when planning an orchard that any saplings that are completely surrounded by trees/other saplings will not grow. It's best to start with 2 rows of the orchard, then the next day add a 3rd row, then the 4th row the following day, and so on. This can cause issues if you're making a perfect fruit orchard as once the tree dies somewhere in the middle you can no longer plant a new one there if it's surrounded. I would suggest keeping any perfect fruit orchards to 2 rows deep at max then leave a few spaces before you plant the next set of rows. That, or line a normal orchard with perfect fruits on the outside edges.