Abstract: To create decorative border arrangements on the ground, a kit of blocks and interconnecting pieces is provided. To assemble the blocks end to end into a row, the opposite end faces of the blocks and the two opposite sides of the interconnecting pieces comprise respective mutually mating interconnecting elements extending transversely of the row and being slidable in each other upon transversal displacement of an interconnecting piece between the confronting end faces of a pair of consecutive blocks, thus fastening the two confronting end faces together. When desired, pickets are used to anchor the blocks to the ground to obtain a semi-permanent construction.