Integrated pest management
Build a proactive pest management ecosystem
Move beyond reactionary spraying. This playbook helps you design an IPM program that starts with prevention, learns from scouting data, leverages biological control, and reserves chemistry for strategic, resistance-aware interventions.
Rethink pest management as ecosystem engineering
Integrated Pest Management replaces calendar spraying with a prevention-first philosophy. You are no longer a chemical applicator; you are an ecosystem manager balancing plant health, natural enemies, and targeted interventions.
Set actionable thresholds
Define the pest count or crop injury level that justifies intervention. Tailor thresholds by crop stage and market tolerance.
Monitor and identify
Scout on a fixed cadence, record exact pest species, and flag hotspots. Accurate ID prevents needless sprays and protects beneficials.
Prevent first
Fortify sanitation, irrigation, nutrition, and exclusion so the greenhouse is hostile to pests before they arrive.
Control with the lightest touch
Escalate from biocontrol to biorational to conventional chemistry only when data proves it is required.
Sanitation: the non-negotiable first line of defense
A spotless greenhouse removes food, shelter, and breeding sites for pests. Treat sanitation as a daily IPM tactic, not occasional housekeeping.
Reset between crops
Empty the house, remove all plant debris, and steam or disinfect benches, tools, and trays before replanting.
Keep floors dry and clear
Eliminate puddles, algae, and spilled media that attract fungus gnats and shore flies. Store hose ends off the ground.
Eliminate weed hosts
Maintain a weed-free zone inside and a bare perimeter outside. Weeds shelter aphids, thrips, and viruses.
Manage waste daily
Use covered bins inside production zones and empty them each day so they never become pest nurseries.
Cultural controls reshape the growing environment
Plants grown under optimal conditions resist pests naturally. Fine-tune irrigation, fertility, and airflow so you avoid creating the stress signals that attract invaders.
Irrigation and humidity discipline
Water based on crop demand, not habit. Avoid late-day irrigation, maintain airflow, and dry foliage overnight to deter fungus gnats and foliar disease.
Nutrient tuning
Test media routinely and feed to the crop’s actual needs. Excess nitrogen creates tender growth that invites aphids and mites.
Quarantine new arrivals
Inspect incoming plugs and cuttings under magnification and isolate them until they clear scouting for eggs, nymphs, and disease symptoms.
Screen the envelope
Install fine-mesh insect screening on vents and intakes. Increase aperture area to maintain airflow while excluding thrips and whiteflies.
Exclusion checklist
- • Fit insect screens (300–400 micron) on vents and sidewalls; expand vent area to maintain CFM.
- • Seal structural gaps around doors, utilities, and gutter joints.
- • Stage footbaths or sanitize footwear between zones.
- • Isolate new plant material for 7–10 days and inspect with a 10× lens.
Tip: Integrate screening data with your ventilation calculations so the HVAC team can compensate for airflow reductions before the season begins.
Scouting turns pest control into a data science
Diligent monitoring provides the intelligence that keeps interventions targeted and cost-effective. Make scouting a fixed part of every production week.
Twice weekly walk-through
Follow a consistent zig-zag route, start at entry doors, and inspect at least 20 plants per 1,000 square feet for 10 minutes.
Use sticky cards as sensors
Deploy one yellow card per 1,000 square feet plus blue cards for thrips hotspots. Record counts and replace cards weekly.
Leverage indicator plants
Stage marigolds, petunias, or banker roses at bench edges to catch early aphid, thrips, or mite activity before it spreads.
Document action thresholds
Use scouting data to set crop-specific trigger points. Propagation stock may tolerate zero pests; finished crops can handle more.
Biological control: cultivate an army of natural enemies
Successful biocontrol programs release beneficials before pests explode and maintain banker plants so allies never leave the greenhouse ecosystem.
| Target pest | Biocontrol options | Deployment notes |
|---|---|---|
| Aphids | Aphidius colemani, Aphidius ervi, Aphidoletes aphidimyza, green lacewings | Combine preventative parasitoid releases with spot treatments of predatory midges when colonies appear. Banker plants sustain populations. |
| Whiteflies | Encarsia formosa, Eretmocerus eremicus, Delphastus catalinae | Match parasitoid species to whitefly type. Supplement with Delphastus when trap counts spike to clean up hot spots. |
| Thrips | Amblyseius cucumeris, Amblyseius swirskii, Orius insidiosus | Predatory mites target first instar larvae; Orius tackles mobile stages. Maintain pollen or banker plants so predators persist. |
| Two-spotted spider mites | Phytoseiulus persimilis, Feltiella acarisuga | Release P. persimilis at the first stippling sign. Add Feltiella for dense hot spots hidden in crop canopies. |
| Fungus gnats | Stratiolaelaps scimitus, Steinernema feltiae, Bti drenches | Layer soil-dwelling predatory mites with nematodes or Bti drenches to eliminate larval stages in moist substrates. |
Banker plant inspiration: suspend barley baskets seeded with non-pest aphids to support the parasitoid Aphidius colemani, or add ornamental peppers to feed Orius with pollen between thrips outbreaks.
Physical tactics and biorationals
Use mechanical suppression and soft chemistries to stay ahead without disrupting beneficials.
- • Blast aphids or whiteflies with a sharp water jet to interrupt feeding cycles.
- • Drench propagation media with Steinernema feltiae or Bti to erase fungus gnat larvae.
- • Apply horticultural oils or insecticidal soaps with full coverage; avoid heat stress windows.
- • Rotate botanical extracts like neem (growth regulator) and pyrethrins (quick knockdown) for diversified impacts.
When chemistry is the final resort
Conventional products remain valuable when thresholds are exceeded and softer controls cannot recover the crop. Make every application count.
- Confirm pest ID and threshold exceedance from scouting data.
- Select the narrowest-spectrum product and follow the label exactly.
- Rotate Mode of Action groups each pest generation to prevent resistance.
- Document date, product, MOA, rate, coverage quality, and results for future planning.
Avoid tank-mixing incompatible MOA groups; it can accelerate resistance by selecting for multi-resistant individuals.
Implementation roadmap
- Audit current sanitation, exclusion, and scouting practices. Close gaps first.
- Set crop-specific action thresholds and build a shared logging template for scouts.
- Roll out preventative biocontrol releases and install banker systems before main crop demand peaks.
- Standardize biorational spray protocols with coverage checklists and compatible beneficial windows.
- Create an MOA rotation chart for emergency chemical use and review it quarterly.
Connect IPM to your broader strategy
Pair this pest management blueprint with complementary guides:
- Equipment blueprint to ensure your structure supports proper airflow, screening, and automation.
- Winter growing guide for cold-season climate tactics that keep humidity and disease in check.
- Ventilation and cooling playbook to reinforce climate controls that support pest prevention.
Frequently Asked Questions
How often should I scout a greenhouse for pests?
Inspect at least weekly—twice weekly is ideal. Follow the same route, log findings, and increase frequency when environmental conditions favor specific pests.
Can biocontrol coexist with limited chemical use?
Yes. Use selective, compatible products and rotate modes of action. Always check product labels for impacts on the beneficial species you rely on.
When should I consider conventional pesticides?
Only after monitoring data shows thresholds surpassed and softer controls fail. Choose the narrowest-spectrum product, follow label rates, and rotate MOA groups to prevent resistance.