Waxy leaves are used for storing water by some plants.
Bromeliads are a group of plants that have stiff, waxy leaves that form a cup-shaped body.
Bromeliads store water in their waxy leaves.
Where do Bromeliads store water?

  at or near the margins
  hard outer covering
  an external framework
  By coral exoskeletons
  In their leaves
  Tropical
  by indirect light
  near the shoreline