Weeds will germinate in regular sand. We use polymeric sand in our patios. My husband and I own a patio business. Sweep it in dry on dry patio. Remove all excess from pavers then mist lightly. Stay off patio for 24 hours. This sand will bond together like concrete and will not blow away or wash out.
With the hose, wash the edging with a gentle spray, dampening the sand between the bricks without dislodging it. As the sand absorbs water, it will set, acting like grout to lock the bricks in place for years to come.
The first project was to build a pebble mosaic carpet. This elaborate design took a month to lay out and set. I first arranged the entire mosaic in a bed of sand on site and then disassembled it and set it in mortar, using forms to break it up in to sections.