The invention is a planar sheet deployment system, primarily for use incultivatingshort-day photoperiodic plants such as cannabis. The system is comprised of:a) a sheet of flexible, planar material suitable for being rolled upon itselffor storage,the sheet material having upper and lower edges and lateral side edges thataredimensioned to cover a predetermined area when deployedb) a frame with an upper horizontal support for anchoring the upper edge ofthesheet material in a generally horizontal alignmentc) a linear winding rod spanning across and bonded to the width of the sheetmaterial along its lower edge in parallel to the upper edge, for winding-upthesheet material into a roll surrounding the winding rodd) a trackway comprising two separated parallel tracks extending from theuppersupport downwardly along respective paths that are displaced inwardly from thelateral edges of the sheet material, extending to a lower level, the trackwaybeingpositioned for supporting the sheet material as the winding rod unrolls theroll ofsheet material while descending towards the unrolled location at that bottomofthe trackwaye) a spool located along at least one end of the winding rod that extendsoutwardlyfrom at least one side edge of the sheet materialf) a winding cord extending down from a point located at the height of anuppersupport portion of the frame and connected at its lower end to the loweredspool-portion on the winding rod, to be wound thereon in the oppositedirectionwith respect to the winding direction of the sheet material, a first portionof thecord being provided to extend from the upper point to the spool when the sheetmaterial is deployed at a fully unrolled location and a second portion of thecord,of similar length, wound onto the spool andg) a cord tensioner for drawing cord upwardly off the spool towards the upperpointwhereby, upon applying tension to the winding cord through the cord tensioner,the winding cord will unspool from the spool on the winding rod caus
