Probably a 9 foot ceiling.
But yeah, you definitely need to hang them from solid wood. That stucco will degrade fast.
Get yourself some high tensile strength string. Run it through a hook on the ceiling (reinforced one, not the stucco, EDIT: or make sure the hooks go through the stucco and into the studs). Then run the string down to a hook on the wall, creating a pulley system. Tie a series of loops into the end of the string where it attaches to the wall loop. Simple system, Jorge-Cervantes-approved. See my very detailed and excellently illustrated Microsoft Paint jpeg below.