The Shovel is a tool needed to grow plants, from apples to wheat to other fruits found on the other islands.Yet certain plants grow on certain land like citrus fruits.
Click on a harvestable food source that has already been in your backpack, such as an Apple or Wheat stalk. Now, you have a Gui that goes along with this tool that says there is 1 content in your shovel. Click on the Gui that says Apple or Wheat or whatever it is you have on your shovel. Then, place the tree or plant whereever you want.
Large Wooden Handle + Stone Shovel Head