Potatoes - Deformation
Symptoms
Edges and tips of the lower leaves become yellow and later necrotic. Eventually, the marginal yellowing spreads between the veins as the deficiency progresses. Leave margins curl up. The leaves often wither and collapse prematurely.
Plant growth is squat and stunted.
Causes
Potassium deficiency
Potatoes - Discolouration
Symptoms
Potassium deficient tubers show black spots. When cut, they blacken rapidly.
The spots mostly occur near the vascular ring at the stolon end of the tuber.
Causes
Black spot due to potassium deficiency
Potatoes - Deformation
Symptoms
Edges and tips of the lower leaves become yellow and later necrotic. Eventually, the marginal yellowing spreads between the veins as the deficiency progresses. Leave margins curl up. The leaves often wither and collapse prematurely.
Plant growth is squat and stunted.
Causes
Potassium deficiency
Potatoes - Deformation
Symptoms
Edges and tips of the lower leaves become yellow and later necrotic. Eventually, the marginal yellowing spreads between the veins as the deficiency progresses. Leave margins curl up. The leaves often wither and collapse prematurely.
Plant growth is squat and stunted.
Causes
Potassium deficiency
Potassium deficiency 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
- Improved yield and quality
- Increased tuber size
- Improved disease resistance
Yara recommended fertilisers for Potassium deficiency
YaraVita FOLIAR POTASH
Potatoes: One application of 10 l/ha or two applications of 5 l/ha during tuber bulking (as soon as first-formed tubers are 10mm in diameter). Allow 10 to 14 days between applications. A further application of 5 l/ha may be made following petiole analysis, during tuber bulking. Water rate: 200 l/ha.
Read more about YaraVita FOLIAR POTASHYaraVita MAGPHOS K
Potatoes: To increase tuber number, 10 l/ha at tuber initiation (when 50% of the tip swellings are twice the diameter of the rest of the stolon). To increase tuber size a minimum of 2 applications of 5 l/ha or 1 to 2 applications of 10 l/ha during tuber bulking (as soon as first formed tubers are 10 mm in diameter). Allow 10-14 days between applications. Water rate: 200 l/ha
Read more about YaraVita MAGPHOS K
