When To Fertilize Palms In Arizona TextAudioPicture

5/8/21 TALKING TREES: #FertilizePalms & the #CarobTree

 Grab a pen and paper, we've got lots of great information to go over!

Tree of the Month: Carob Tree | Scientific Name: Ceratonia siliqua

May's Tree Tips & When To #FertilizePalms In AZ

  • Rosie on the House Queen PalmsAll heavy cutbacks should have been completed by now.
    • You might get away with some radical pruning but the plants could get sunburned.
  • May and June are great months to prune your fast-growing trees to reduce risk of monsoon storm damage.
  • Removing the proper percentage of foliage is as important as timing:
    • The rule of thumb is that you can remove a larger percentage of foliage from younger, faster-growing trees.
    • Take it easier on older, slower-growing trees, regardless of the season.
  • Check young or newly planted trees for proper staking and tie adjustments in preparation for summer storms.
  • It is time for your next fertilizer application, or get it on the schedule as soon as possible.


  • Don’t forget to fertilize your palms, especially Queen Palms, through the growing season, starting now (May), through September.
    • Palms are often deficient in certain micronutrients such as Magnesium (Mg), Manganese (Mn), Zinc (Z), and Iron (Fe).
    • Be sure your palm fertilizer includes these micronutrients in addition to a 3-1-3 ratio of Nitrogen, Phosphorus, and Potassium (NPK).
  • The best method of fertilizing is by soil drench with a liquid fertilizer.
    • You should fertilize by deep root injection only when needed, such as to get fertilizer past lawn roots.
    • Fertilizer spikes are ok but granular fertilizer can more evenly be distributed across the entire root zone.
    • Solid fertilizers must be watered in to be effective.
  • Soil additives are an essential component of a comprehensive plant health program.
    • These include mycorrhizae, beneficial bacteria, plant growth regulators, pH buffering agents, soil conditioners/salt remediation, and liquid organic matter.
    • Consult a Certified Arborist for more details or to schedule a soil sample, lab analysis, and treatment prescription.
  • Take a close look at your trees, shrubs, and lawn and make note of any heavy insect populations.
  • Dates Palms are trimmed after May 15th – 90 degrees
  • Mexican Fan Palms are trimmed after June 15th – 90 degrees or less
  • California Fan Palms are trimmed after July 15th – 90 degrees or less
  • Queen Palms are trimmed all year, seed pods and dead fronds only

Definition of Psithurism: The sound of wind rustling in the leaves


Expert John Eisenhower discuss the Tree Of The Month: The Carob Tree! An evergreen shade tree most landscapes never think about. And yes, its pods are edible and can be used for cocoa. Plus tips on fertilizing palms and listener questions including help with an ailing aleppo pine, watering a young red push pistache, pruning a chilean mesquite and a mystery solved! What are the holes in the trunk of my carob tree?