Agricultural and/or horticultural greenhouse (1) for cultivating crops therein, wherein at least a part of the greenhouse is provided close to the upper side with at least one horizontally suspended fabric screen (21,22) which defines in that part a cultivation space (12) for cultivating crops therein under the fabric screen and a ridge space (13) separated from the cultivation space (12), wherein the fabric screen comprises at least one passage (24) between the ridge space (13) and the cultivation space (12), wherein the greenhouse further comprises a ventilation system with air displacing means (31) for displacing air in the cultivation space of the greenhouse, wherein at least one of the air displacing means (31) is situated close to the passage (24) in the fabric screen (21,22) and is configured to draw in and subsequently displace air from both the ridge space and the cultivation space.
