Biological Controls in Commercial Nurseries

Biological Controls in Commercial Nurseries: Why IPM IS Becoming Best Practice

Across Australia’s nursery industry, pest and disease management is getting harder to do well using the old approach alone.

For many production nurseries, relying too heavily on spray programs is becoming less effective, more expensive and harder to sustain over time. Resistance is building, chemical options are tightening, and more businesses are realising that repeated reactive spraying is not the same as having a strong pest management system.

That is where biological control is becoming more important.

This is not about replacing chemistry altogether. It is about building a more balanced and effective Integrated Pest Management (IPM) program that gives nurseries better long term control, better crop consistency and fewer pest blowouts.

And importantly, this approach already aligns with what industry best practice is asking for.

Biological Control Sits Within NIASA Best Practice 

Under the Nursery Industry Accreditation Scheme Australia (NIASA), pest and disease management is not treated as a one off response when something goes wrong. It is part of a broader system that includes:

• crop hygiene
• monitoring and inspection
• environmental management
• responsible chemical use
• prevention of pathogen spread

That matters, because most nursery pest issues do not start with a lack of spraying. They usually start with pressure building quietly through poor monitoring, hygiene gaps, crop stress, contaminated inputs or delayed action.

Biological control works well in this kind of system because it is preventative by nature. It helps keep pest numbers below damaging levels, rather than waiting until they are already out of hand.

What Biological Control Looks Like In Practice Biological control is already being used in Australian nursery production across a wide range of crops and systems. That can include: Predatory mites for thrips and two spotted mite Parasitoid wasps for aphids and whitefly Beneficial nematodes for fungus gnats and soil pests Microbial biologicals for soilborne disease suppression These are not niche or experimental tools. They are already being used commercially in Australian nurseries supported by providers such as Biological Services and through technical resources like the Garden City Plastics Agronomy Solution Finder (ASF) platform. Both highlight the range of nursery relevant pests that can be managed biologically, including thrips, whitefly, aphids, fungus gnats, mealybug and scale.

Why more nurseries are moving this way

There are a few very practical reasons more nurseries are moving this way.

Resistance is becoming harder to ignore
Repeated use of the same chemical groups is reducing effectiveness, particularly for high pressure pests like thrips and whitefly which can become a big problem quickly.

Biosecurity and hygiene expectations are higher
NIASA guidelines are putting more focus on prevention, not just treatment. That includes sanitation, crop movement, propagation hygiene and reducing pest carryover between areas.

Chemical access is tightening
Regulatory reviews continue to impact available actives, requiring more strategic use of chemistry.

Production costs are rising
When labour, fuel and inputs are already high, pest outbreaks become even more expensive. Re spraying, crop losses, labour time and inconsistency through the crop all add up.

Biological control addresses all four.

Where Biological Programs Succeed or Fail

The biggest mistake some businesses make is assuming biologicals are just another product to apply.
They are not. Like anything in nursery production, they only work properly when the system around them is right.

What works:

• introducing beneficials early
• monitoring crops consistently
• using sticky traps and regular scouting
• maintaining strong hygiene and sanitation
• using compatible chemistry where needed
• making sure staff can identify pests and beneficials properly
• waiting until there is already a visible outbreak
• treating biologicals like a rescue spray
• running spray programs that wipe beneficials out
• poor record keeping
• not knowing what pest pressure is actually doing week to week\

What does not
NIASA reinforces that understanding pest and disease lifecycles, and maintaining hygiene systems, is critical to preventing outbreaks in the first place.

That principle is fundamental to biological control.

The Commercial Value Is In Consistency

For most nurseries, this is not just about being “greener”.
It is about building a production system that is more stable, more predictable and less reactive.

A well run IPM program that includes biological control can help reduce resistance pressure, improve crop consistency, lower the risk of major flare ups and support a more measured use of chemistry over time.

That is especially valuable in propagation, protected cropping and higher value production where pest pressure can escalate quickly.