Identifying nutritional deficiencies in backyard plants

Page last updated: Monday, 13 August 2018 - 4:49pm

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Nutrition is an important component of plant health. A nutrient deficiency will reduce a plant’s ability to complete its life cycle of producing flowers and fruits. This web article describes the symptoms of common deficiencies to enable the home gardener to make a diagnosis.

Deficiency symptoms

It is not uncommon for plants to suffer from a combination of deficiencies. Some visible symptoms include:

  • discoloration or premature dying of leaves
  • stunting of growth
  • blemishes on fruits
  • undeveloped root systems.

Plants can also suffer from nutrient toxicity if an excess of a nutrient is applied. 

Plant disorders with similar symptoms

Check that the following symptoms are not the cause:

  • a pests or a disease
  • salinity
  • herbicide drift
  • physiological conditions
  • environmental conditions.

Nutrient mobility

Nutrients such as nitrogen, phosphorus, potassium and magnesium are readily translocated within the plant and are referred to as “mobile”. Symptoms first appear on older leaves as the nutrients are moved to new growth. Other nutrients such as iron, zinc, calcium and boron are immobile and are not moved around the plant, with symptoms generally occurring on the growing tips. Manganese mobility is complex and depends on the species and the age of the plant and the deficiency may appear on either old or new leaves.