Water Management in Horticultural Crops

Crop coefficients for different growth stages

• Crop coefficient (Kc) value varies with the development stage of the crop.
  
• For most crops the value for total growing period is between 0.85 and 0.9 with the exception of higher value for banana, coffee and cocoa and lower value for citrus, grape, sisal and pineapple.
• In general, Kc is higher in hot, windy and dry climates than in cool, calm and humid climates.
  
• The values vary among crops due differences in reflectivity, crop height and roughness, degree of ground cover and canopy resistance to transpiration.
  
• In the case of annual crops , kc typically increase from a low value at seedling emergence to a maximum when the crop reaches full ground cover, continues at that value during the stage of full activity and declines as the crop matures.
For further reading the students may refer

• Doorenbos J and Pruit WO1977.Crop water requirements. Irrigation and drainage paper 24. FAO,Rome, Italy.
  Doorebos J and Kassam AH 1979.Yield responses to water. Irrigation and drainage paper 33. FAO,Rome, Italy.