Experts and BHG readers answer.
Planting a fruit tree
You don't say where you live so it's important for you to know that in the north, citrus makes a great addition to your garden, but it must be brought indoors during the winter. And, yes, you can plant a dwarf orange in a 3 foot planter and you can probably plant very close to it. Spacing kind of depends on what you plan to plant with it. Just plant your citrus at the same depth it was growing in the pot you bought it in.