Open Grow Bags are the preferred choice as a space-saving growing medium, usually used in greenhouse cultivation. Trellis Grow Bags are compressed slabs of coco air wrapped in a polythene bag that is either white or black. These multipurpose grow bags are filled with fine-grade coco peat. The slab when placed inside a bag expands and fills the bag once water is added. They are available in different sizes, blends, formats and are customisable to your requirements.