Nutrients

N Nitrogen
P Phosphorus
K Potassium
Mg Magnesium
Ca Calcium
S Sulphur
B Boron
Cu Copper
Fe Iron
Mn Manganese
Mo Molybdenum
Zn Zinc

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.

Reasons
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.

Reasons
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.

Reasons
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.

Reasons
Potassium deficiency.

Potatoes - Chlorosis

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. At the same time the leaf veins may turn brown as well. Leave margins curl up. The leaves often wither and collapse prematurely. Plant growth is squat and stunted.

Reasons
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 fertilizers for Potassium

YaraVita® AGRIPOTASH™

YaraVita® AGRIPOTASH™

Potatoes: One application of 10 l/ha or two applications of 5 l/ha during tuber bulking (as soon as first formed tuber are 10 mm in diameter). Allow 10-14 days between applications. Water rate: 200 l/ha. Pommes de Terre: Une application de 10 l/ha ou 2 applications de 5 l/ha pendant le grossissement (dés le stade premiers tubercules 10 mm de diamétre). Laisser 10-14 jours entre applications. Volume d'eau: 200 l/ha.

Read more about YaraVita® AGRIPOTASH™