PLANT GROWTH SYSTEM

The disclosure relates to a plant growth system (1) comprising: • - a water impermeable container (2) having a base and side walls, wherein the water impermeable container comprises within: • (i) a layer of buffer material (3) for absorbing storm water and; • (ii) a first void space (4); wherein the layer of buffer material has a first side surface, a second side surface and a bottom surface, wherein the bottom surface of the layer of buffer material is in direct contact with the base of the water impermeable container and wherein the buffer material comprises man-made vitreous fibres (MMVF) bonded with a cured binder composition wherein the first void space is in fluid communication with the first side surface of the layer of buffer material; • - an inlet (5) for water to enter the first void space of the water impermeable container; • - a plant growth substrate layer (6), positioned above the layer of buffer material and in fluid communication with the layer of buffer material.