Keep your plants warm and protected throughout the harsh winter months with this Fleece Greenhouse Cover from Christow. The cover is designed to keep plants warm to a minimum temperature of -8˚C and comes in two sizes to fit Christow 3 tier and 4 tier greenhouses. Extra-Thick Fleece The cover has a thickness of 65gsm for ultimate warmth and insulation. Despite its thickness, the cover is breathable to give plants the ventilation they require for strong, healthy growth