Expansion bolts (also called molly bolts) are similar to anchors, except that once the screw is run through the anchor unit, the unit expands behind the wall, creating a true anchor that won't allow the screw to be pulled out by the weight of the item.
The heavy cardboard casting tube (a form for pouring concrete columns) was wrapped in thin galvanized sheet metal;
expansion bolts secure the vertical seam on the back.
Using the longer nails, anchor the two back wall supports to studs (if the small end supports don't span two studs, you may need
expansion bolts to secure them).
Woodscrews attach the central piece to a wall stud;
expansion bolts secure branches to the gypsum board wall.
When plants reach full bloom, in early July, they are secured to the wall with clips and
expansion bolts (see photograph at bottom right).
(Sockets may require
expansion bolts instead of the screws supplied.)
