Onions - Growth retardation
Symptoms
Plant growth and establishment is delayed.
Rooting is adversely affected and stunted.
Causes
Phosphorus Deficiency
P is rarely required in large quantities.
Onions - Growth retardation
Symptoms
Plant growth and establishment is delayed.
Rooting is adversely affected and stunted.
Causes
Phosphorus Deficiency
P is rarely required in large quantities.
Phosphorus deficiency made worse by
- Acidic or very alkaline (calcareaus) soils
- Low organic matter
- Cold or wet conditions
- Crops with a poorly developed root system
- Soils with low P reserves
- Soils with a high phosphate capacity
- Iron rich soils
Phosphorus is important for
- Essential for energy transfer within the plant, therefore direct effect on yield and quality
- Boosts yield and bulb size
- Helps ensuring top yields through use of high rates of N with little quality deterioration
