Potassium deficiency on orange made worse by

  • Acidic soils (low pH)
  • Sandy or light soils (leaching)
  • Drought conditions
  • High rainfall (leaching)
  • or heavy irrigation
  • Heavy clay (illite) soils
  • Soils with low K reserves
  • Magnesium rich soils

Potassium is important for

  • Larger leaf area maintaining through season
  • Shoot growth more vigorous
  • Fruit load increase/benifit to yield
  • Fruit are larger with better colour, skin texture and flavouring (more acidity)
  • Level of vitamin C increases