Container and Production Bed Mulch Effects on Media Temperatures and Growth of ‘Hershey’s Red’ Azalea

Three pot/mulch combinations and 2 pot spacings were evaluated as to their effects on growing-media temperatures and growth of ‘Hershey’s Red’ azalea ( Rhododendron Xsp.). The highest, maximum temperature and least root and shoot growth occurred in black pots on white clam shell mulch compared to white pots on black polyethylene and to white plywood-shielded pots. Close spacings of pots increased root growth with black pots on white mulch but not with white pots on black mulch. Plants in black pots on white mulch developed the greatest winter foliage discoloration and leaf abscission.