Grow grids can prevent staining amp algae growth on patios amp wooden deck surfaces which can be a common ocurrence when using grow bags or patio planting bags the 2 grids in the pack can be connected to provide an area 96 x 355 cm the perfect area for a standard uk grow bag r grow grids can be connected together in either direction allowing you to build an area to your own requirements these grids support the planter above the floor surface allowing air to circulate and permitting