Re-pot your plant every two years, in the spring, only if the base of the stem encroaches upon the edge of the pot. Generally, a clean pot of the next size up with fresh soil is fine as the plant grows slowly. Moving to too large a pot risks root and stem rot. 

Handle the plant carefully as you move it so as not to damage the roots. Keep the plant in a pot with a drain hole and a run-off dish that is not attached to the container. Do not set the plant any more deeply into the potting soil than it has been growing in its old pot; burying the stem will lead to rot.

Ponytail palm likes a gritty soil and relatively small pot with excellent drainage. A cactus potting medium with no added fertilizer or a mix of three parts grit or sand (for drainage) with one part potting soil (for organic material) and a small amount of coir or shredded bark (for texture) make suitable soils. Plants that are potted in the wrong mixture will initially do well but may later suffer from root rot associated with excess water retention in the soil.  A thin spread of grit or small pebbles as the top layer of the potting mixture is helpful to prevent stem and leaf contact with wet soil.

You can read more about this plant and its care in our Guide to Ponytail Palm Houseplants.

Courtesy of NYBG Plant Information Service