Nutrients

P Phosphorus
K Potassium
Mg Magnesium
Ca Calcium
S Sulfur
B Boron
Fe Iron
Mn Manganese
Zn Zinc

Apples - Chlorosis

Symptoms
Terminal buds die off. The youngest leaves first turn slightly chlorotic, then margins become scorched and roll inwards.

Reasons
Boron deficiency

Apples - Deformation

Symptoms
Fruits show corking disorders and are often small and deformed.

Reasons
Boron deficiency Symptoms can be confused with calcium deficiency. But boron deficiency causes symptoms in early state of fruit development, while calcium deficiency gives symptoms a few weeks before harvesting or in store.

Apples - Deformation

Symptoms
Fruits are small and deformed and necrotic with sunken areas which give a dimpled appearance

Reasons
Severe boron deficiency Symptoms can be confused with apple scab (caused by Venturia inaequalis)

Apples - Deformation

Symptoms
Fruits with boron deficiency (left hand side) compared with healthy fruits. Fruits show corking disorders and some are small and deformed.

Reasons
Boron deficiency Symptoms can be confused with calcium deficiency. But boron deficiency causes symptoms in early state of fruit development, while calcium deficiency gives symptomes a few weeks before harvesting or in store.

Apples - Deformation

Symptoms
Surface of fruits shows corky areas and cracks. Fruits are often small and deformed.

Reasons
Severe boron deficiency Symptoms can be confused with apple scrap (caused by Venturia inaequalis)

Apples - Corky areas

Symptoms
Corky spots appear on the bark of lateral shoots.

Reasons
Boron deficiency

Apples - Cracking

Symptoms
Surface of fruits shows corky areas and cracks. Fruits are often small and deformed.

Reasons
Severe boron deficiency Symptoms can be confused with apple scrap (caused by Venturia inaequalis)

Boron deficiency made worse by

  • Sandy soils
  • Alkaline soils
  • Soils low in organic matter
  • High levels of nitrogen
  • High levels of calcium
  • Cold wet weather
  • Periods of drought

Boron is important for

  • Improves bud development
  • Improves flowering
  • Improves fruit set
  • Gives better skin finish
  • Reduces storage disorders

Yara recommended fertilizers for Boron

YaraVita® BUD BUILDER™WP

YaraVita® BUD BUILDER™WP

Apples: In the Spring apply 5 to 10 lbs/acre applied at bud burst. Reapply after fruit set during sizing in 10 to 14 day intervals. 5-10 lbs/acre applied post-harvest before leaf senescence. Water rate: minimum 25 gallons/acre. Foliar application of Bud Builder may leave a white residue-deposit on the leaf or crop when applied close to harvest.

Read more about YaraVita® BUD BUILDER™WP

YaraVita® POWERBOR™ Ca

YaraVita® POWERBOR™ Ca

Apple: Several applications of 1 to 2 quarts/acre beginning at pink bud, start of flowering, at petal fall, after fruit set and during sizing. Also, after harvest but before leaf senescence. Water rate: 15 gallons per acre minimum.

Read more about YaraVita® POWERBOR™ Ca