Thrips

Overview

Thrips are major pests in protected crops, often peaking in spring when conditions turn bright and dry.

Symptoms

• Silvering / scarring on leaves
• Distorted growth
• Flower damage

Conditions that increase risk

• Hot Dry Weather
• Spring flush

Biological control options

• Orius laevigatus
• Amblyseius swirskii

Notes (field experience)

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Orius species nuance (commercial practice)

• Orius laevigatus is typically strongest once crops are flowering and flower thrips dominate.
• Orius majusculus is often preferred for leaf thrips or cooler conditions.

Baseline larval suppression is commonly provided by: - Amblyseius cucumeris - Amblyseius swirskii

• Amblyseius montdorensis is a strong alternative to swirskii, often performing better under slightly cooler conditions.

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Further guidance

• Thrips — Biocontrol Foundations

Key natural enemies

• Orius laevigatus
• Orius majusculus
• Amblyseius cucumeris
• Amblyseius swirskii

Environmental drivers

• Often increases in warm, dry conditions; pressure commonly rises through spring into summer.
• Flowering crops can sustain higher populations due to pollen feeding.
• Pupation in soil/media means substrate conditions and soil predators can matter.