Capsid Bug

Integrated IPM approaches.

Capsid bugs cause pitting and distortion; biological strategies focus on early detection...

About Capsid Bugs

Capsid bugs — particularly Lygus and Polymerus species — are piercing-sucking pests that cause serious distortion to soft growing tips, young fruit and ornamental crops. They inject toxic saliva into plant tissue, causing cells to collapse, resulting in the distinctive “blind buds”, puckering, scarring and misshapen growth that growers often struggle to diagnose.

Capsids are fast-moving, easily disturbed and difficult to spot. They hide deep within the canopy and feed rapidly during warm periods, making early detection critical in propagation units, cut flower production and high-value ornamentals.

Symptoms of Capsid Bug Damage

• Brown, corky lesions on young stems or leaves
• Distorted new growth (“puckering” or “crumpling”)
• Small sunken pits on fruit or soft stems
• “Blind buds” where flowers or shoots abort
• Random shot-hole damage caused by feeding punctures
• Leaf cupping or twisting on vigorous crops

Why Biological Control Works

Although no single beneficial insect specialises in capsid control, an integrated programme combining habitat manipulation, early monitoring and generalist predators can significantly reduce pressure. Predators such as Orius, lacewings and ladybirds feed on young nymphs, while maintaining high biodiversity helps prevent population surges commonly seen in enclosed ornamental production.

Common UK Capsid Bug Species

• Lygus rugulipennis (European tarnished plant bug)
• Polymerus spp. (Green capsid complex)
• Liocoris tripustulatus (Common capsid in ornamentals)
• Plesiocoris spp. (Occasional protected crop pest)

IPM Recommendations

• Use sticky traps to detect adults early in the season
• Introduce generalist predators preventatively
• Remove weeds inside and outside structures — key hosts
• Inspect growing tips weekly for small feeding pits
• Maintain netting or screening in propagation areas
• Manage humidity and dense growth to reduce hiding sites

Preventative vs Curative Strategy

Preventative:

• Deploy yellow sticky traps along doors and vents to detect early flights.
• Encourage generalist predators such as lacewings early in the canopy.
• Maintain strict weed management around tunnels and glasshouses.

Curative:

• Spot-treat hotspots with compatible sprays if nymphs are present.
• Increase predator activity with supplementary releases where viable.
• Prune out badly distorted growing points to remove feeding sites.
• Strengthen airflow in affected areas to reduce pest shelter.

Environmental Notes

• Warm, dry weather accelerates capsid feeding and movement
• Adults frequently migrate in from outside weeds and hedgerows
• Dense ornamentals with soft new growth are most at risk
• Weed hosts include chickweed, nettles, fat hen and clover