This modern black tree planter is constructed of fiber-reinforced concrete, so it has strength and durability without quite as much weight. At 21" high, the simple yet contemporary square design with a matte black finish is perfectly proportioned for a 6 - 10 foot tree. Fits any plant inside a nursery pot that is 12" or smaller. Interior dimensions: 14" long x 14" wide. Overall dimensions: 18.5" long x 18.5" wide x 21" high