• Changes affecting fruit set start in preceding summer.
  • Sufficient water during preceding summer assists the change from vegetative buds into flower buds.
  • Stress from water shortage, pests, diseases and nutrient deficiency can severely affect fruit development and yield.
  • Flowering usually occurs in September and October, depending on variety and conditions.
  • July and August are critical for ensuring tree is in peak condition.
  • Dry-land trees can have as many as 52% sterile flowers, compared to suitably irrigated trees with 7-8%.
  • Trees must be exposed to winter chill to bear fruit.
  • Average temperature for July should be 12 degrees Celsius or less for adequate chilling.
  • Hot dry winds during flowering will tend to increase flower drop and reduce fruit set.
  • Olive trees in suitable environments produce abundant pollen.
  • Correct irrigation and windbreaks reduce the detrimental effects of heat and wind on fruit set.