Copper (Cu)

Role in plants

Copper is involved in electron transport, lignin formation, and oxidative stress defence. It supports structural strength and reproductive development.

Deficiency symptoms

• Dieback of shoot tips
• Poor lignification (weak stems)
• Leaf twisting or distortion
• Reduced flowering/fruit set

Toxicity symptoms

• Root damage and reduced root growth
• Chlorosis and leaf burn
• Strongly inhibitory to microbes at high concentrations

Natural sources

• Soil minerals
• Organic matter complexes

Fertiliser sources

• Copper sulphate (careful: narrow safety margin)
• Chelated Cu products

Plant uptake forms

• Cu²⁺ (and complexed forms)