A foldable protective cover, comprising: longitudinal rows of posts (1); longitudinal fixed cables (2a, 2b) arranged parallel to the rows of posts (1); and a series of longitudinally aligned sections of protective sheet (3), each section of sheet (3) being having a first end (31) secured to the fixed cables (2a, 2b); and a second end (32) fixed to movable cables (4a, 4b), the opposite ends of said movable cables being fixed to means for winding and unwinding that longitudinally move these movable cables over a distance approximately equal to the length of one section of sheet (3), between: a closed position, in which the sections of sheet (3) are unfolded; and an open position, in which the sections of sheet (3) are folded longitudinally against their respective first fixed end (31).