April 2013 Pest of the Month

Boron Deficiency

  • Hosts: Palms
  • Symptoms Twists or bends in the stems, failure of apical meristems to fully open and expand, and leaf wrinkling or crumpling known as “accordion leaf”. There may be chlorosis in young leaves, shortening of terminal internodes, or “scorched” leaf tips.  Fruits may abort prematurely due to functional failure of pollen tubes.  In certain species, transverse, translucent streaking.  In some cases, necrotic truncation of leaves may result in an inverted “V” shape.
  • Diagnosis: Through observation of symptoms.
  • Prevention: Apply fertilizer twice a year with specially formulated palm fertilizers that include minor elements.  Irrigate fertilized plants, particularly in low rainfall areas.  Recognize that boron deficiency is more common in very wet or very dry conditions and apply fertilizer accordingly.
  • Treatment: Apply a boron drench to the root symptoms.  Don’t apply too much – too much boron will severely damage or kill a plant.  Follow the product instructions.

Source: Erik Patnude and Scot Nelson, CTAHR, University of Hawaii at Manoa, April 2012, http://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-83.pdf

Boron Deficiency – photo by Scot Nelson