A greenhouse covering system comprising a connection member 300 configured to be connected to a frame of a greenhouse and a plastics sheet 200 suitable for a greenhouse covering, which plastics sheet is configured to be connected to the connection member by sliding engagement therewith. The plastic sheet may have a profile 206 on at least one edge for connection to the connection member. The plastic sheet may comprise two layers which form a closed pocket and the system may further include a blower port for inflating the inflating the two-layer sheet. A method of covering a greenhouse may include attaching the sheet to an existing sheet on the greenhouse frame and pulling the sheet onto the frame by pulling the existing sheet off.
