Herb Crop IPM Module
Practical IPM plan for culinary herbs covering basil, mint, coriander, parsley, chives and mixed protected herb production.
This page focuses on aphids, thrips, whitefly, spider mite, mildew, Botrytis and crop hygiene.
Quick summary
Main pest risks
Aphids, thrips, whitefly, spider mite and sciarid fly.
Main disease pressure
Botrytis, mildew and damping-off increase in dense humid crops.
Main IPM principle
Keep crops clean, balanced and actively growing without creating excessive humidity.
Herb crops are often fast-turnaround crops with soft tissue and dense canopy growth.
This means pest populations can establish rapidly, especially in: - warm protected environments - propagation areas - high-density production - continuously cropped systems
Main pest risks
| Pest | Risk level | Key trigger | Inspect |
|---|---|---|---|
| Aphids | High | Soft growth and dense crops | Growing tips and undersides |
| Thrips | Moderate–High | Warm protected crops | Flowers and growing points |
| Whitefly | Moderate | Crop carryover and warm conditions | Lower leaves |
| Spider mites | Moderate | Hot dry crops | Lower leaves |
| Sciarid fly | Moderate | Wet propagation and substrate | Compost surface |
| Leafminer | Moderate | Protected crops | Leaf mines |
| Mildew | Moderate–High | Humidity and airflow problems | Leaf surfaces |
| Botrytis | Moderate | Dense humid canopy | Older tissue and stem bases |
Crop stage plan
| Crop stage | Main risk | Practical focus |
|---|---|---|
| Propagation | Sciarid fly, damping-off, aphids | Clean trays and substrate monitoring |
| Young crop | Aphids and whitefly | Sticky traps and early biologicals |
| Rapid vegetative growth | Aphids, mildew and Botrytis | Airflow and crop balance |
| Harvest stage | Thrips and contamination risk | Clean picking and hotspot monitoring |
| Warm weather | Spider mite and thrips | Increased inspections |
| Dense crop phase | Botrytis and mildew | Reduce humidity and improve airflow |
| Crop turnover | Carryover pests | Clean-down and sanitation |
Monitoring plan
| Area | What to look for | Frequency |
|---|---|---|
| Growing tips | Aphids and distortion | Weekly |
| Lower leaves | Whitefly and spider mite | Weekly |
| Flowers and heads | Thrips | Weekly |
| Sticky traps | Flying pests and pressure changes | Weekly |
| Substrate surface | Sciarid fly and algae | Weekly |
| Dense canopy areas | Mildew and Botrytis | Weekly |
| Propagation areas | Damping-off and pest carryover | Every visit |
Environmental risk
| Condition | Likely issue | Management response |
|---|---|---|
| Soft rapid growth | Aphids | Review nitrogen and crop balance |
| Warm protected crop | Thrips and whitefly | Increase monitoring |
| Hot dry conditions | Spider mite | Reduce stress and inspect lower leaves |
| Dense humid canopy | Botrytis and mildew | Improve airflow |
| Wet propagation media | Sciarid fly and damping-off | Improve dry-down |
| Crop overlap | Whitefly and aphid carryover | Clean crop transitions |
| Poor airflow | Hidden hotspots | Open canopy and improve ventilation |
Biological control programme
Preventative phase
Focus on:
- clean propagation
- sticky trap monitoring
- early predator establishment
- avoiding excessive humidity
- balanced irrigation and nutrition
- reducing crop carryover
Active crop phase
During production:
- inspect crops weekly
- monitor hotspots separately
- maintain beneficial continuity
- avoid unnecessary disruptive chemistry
- remove heavily infested plants where practical
High-risk warm periods
During warm conditions:
- increase spider mite inspections
- monitor flowers for thrips
- check dry crop edges
- maintain airflow and irrigation consistency
Pest-specific notes
Aphids
Aphids are often the main herb crop pest.
Key actions:
- inspect shoot tips
- monitor soft growth
- preserve parasitoids and predators
- avoid excessive nitrogen
- respond early to colonies
Thrips
Thrips are common in warm protected herb crops.
Key actions:
- inspect flowers and growing points
- monitor sticky traps
- maintain predators
- avoid hidden hotspots in dense growth
Whitefly
Whitefly may persist between herb crop cycles.
Key actions:
- inspect lower leaves
- avoid crop carryover
- maintain sticky trap monitoring
- support biological continuity
Spider mites
Spider mites increase during hot dry periods.
Key actions:
- inspect lower leaves
- monitor dry edges
- reduce plant stress
- respond before webbing develops
Sciarid fly
Sciarid fly is most important in propagation and wet substrate systems.
Key actions:
- avoid overwatering
- manage algae
- inspect propagation areas carefully
- maintain dry-down periods where possible
Leafminer
Leafminer can affect visual quality.
Key actions:
- inspect leaves regularly
- remove heavily mined leaves
- monitor adult activity on traps
- preserve parasitoids
Disease and hygiene notes
Herb crops are vulnerable to:
- Botrytis
- mildew
- damping-off
- humidity-related decline
Useful actions:
- improve airflow
- avoid prolonged wet foliage
- reduce overcrowding
- remove old tissue
- maintain clean propagation systems
- avoid leaving crop waste in production areas
Canopy and hygiene
Good herb crop management improves:
- airflow
- crop dry-down
- monitoring visibility
- disease prevention
- harvest cleanliness
Useful practices:
- avoid overcrowding
- keep pathways clean
- remove old plant material
- reduce algae
- clean trays and benches
- maintain separation between crop batches
Seasonal calendar
| Period | Main IPM focus |
|---|---|
| Propagation | Hygiene and sciarid fly prevention |
| Young crop | Aphids and whitefly |
| Rapid growth | Crop balance and airflow |
| Warm weather | Thrips and spider mite |
| Dense canopy | Botrytis and mildew prevention |
| Harvest phase | Clean picking and hotspot checks |
| Crop turnover | Clean-down and sanitation |
Linked tools
Use this module alongside:
Key message
Herb IPM is based around cleanliness, airflow and fast response.
Because herb crops grow quickly and are often sold fresh, small pest or disease problems can rapidly become commercial quality issues. Prevention, monitoring and hygiene are the foundation of successful herb crop IPM.