Nitrogen deficiency vs. optimum made worse by
- Low or high pH soils
 - Sandy or light soils (leaching
 - ) Low organic matter
 - Drought conditions
 - High rainfall (leaching) or heavy irrigation
 - Addition or high levels of non-decomposed organic matter/manure (eg straw)
 - Fast growing crops
 
Nitrogen is important for
- Promotes root and shoot development
 - Strong growth, fruit set, fruit size and quality