How long does Cedar last as a box garden?
Cedar and redwood are the best natural materials for box gardens because the resist rot and insect manifestations. How long they last will depend on the climate. In wet climates, it will not last as long as in dry desert climates. It also depends on how much watering takes place in the box garden.
In dry climates cedar and redwood can last up to 20 years. In wet climates, it may only last 8-10 years.
If you live in a wet climate, the best box garden material is stone, brick or rock. These materials will last forever.