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Fungal diseases remain one of the most persistent production risks for Kenyan farmers. Coffee leaf rust can reduce the productive leaf area of coffee trees. Tea plantations must manage diseases such as blister blight and brown blight. Flower farms face constant pressure from Botrytis and other fungal diseases, while vegetable growers regularly deal with a wide range of foliar, fruit and soil-borne pathogens.

For many commercial farms, the traditional response has been straightforward:

Disease pressure increases → apply another fungicide.

Chemical fungicides remain extremely important agricultural tools and, under severe disease pressure, they can be indispensable. However, modern disease management increasingly requires a more sophisticated question: Should a farm rely entirely on chemical fungicides, switch to biological protection, or combine both?

For many Kenyan farms, the strongest commercial strategy is not an “either/or” decision. It is: Chemical control + biological protection + Integrated Pest Management

The objective is not to eliminate chemistry at any cost. The objective is to achieve reliable disease control while managing resistance risk, pesticide expenditure, residues, environmental pressure and long-term crop health.

Why Farmers Are Reconsidering Fungicide Programmes

A fungicide programme should ultimately protect the farm's profitability. That means protecting:

• yield;
• crop quality;
• exportable or marketable percentage;
• productive leaf area;
• fruit quality;
• stem quality in flowers;
• harvest continuity.

Chemical fungicides can provide fast and highly effective disease control when used correctly. The problem begins when the same chemistry or fungicides with similar modes of action are used repeatedly.

The Fungicide Resistance Action Committee, or FRAC, specifically advises against exclusive reliance on the same fungicide chemistry and recommends appropriate rotation, alternation or combinations involving different modes of action as part of resistance-management strategies. This is important because disease control is not only about what works today. It is also about preserving the effectiveness of available fungicides for future seasons.

What Is Fungicide Resistance?

Fungal populations are not genetically identical. When a fungicide with the same mode of action is repeatedly applied, susceptible individuals are controlled, while less sensitive individuals may survive and reproduce. Over time, repeated selection pressure can increase the proportion of less-sensitive or resistant individuals within the pathogen population.

This can eventually result in:

• reduced fungicide performance;
• shorter periods of control;
• increased application frequency;
• higher treatment costs;
• the need to introduce alternative active ingredients;
• in serious cases, loss of an important disease-management tool.

FAO resistance-management guidance identifies integrated disease management, appropriate cultural practices, biological control agents and responsible fungicide use among the measures that can help reduce resistance pressure.

This is one reason biological crop-protection products are becoming increasingly relevant. Not because chemical fungicides have become unnecessary. But because relying on chemistry alone can create long-term agronomic and commercial risks.

Biological Fungicides vs Chemical Fungicides: What Is the Difference?

The two approaches should not automatically be viewed as competitors. They often perform different functions within the crop-protection programme. Chemical fungicides may kill the pathogen, inhibit essential biological processes or prevent fungal development through specific biochemical mechanisms.

Biological crop-protection products may use microorganisms or their biological activity to suppress pathogens, compete for space and resources, support plant defence mechanisms or help create an environment less favourable to disease development.

FAO recognises biological pest-control agents as potential components of Integrated Pest Management programmes and notes that microbial biological control products can complement wider plant-protection strategies.

For a commercial farm, the important question is therefore:Which tool should be used, and at what stage of disease development?

 

Chemical Fungicides vs EcoRic Biological Programme

A practical comparison can be summarised as follows.

Parameter	Chemical Fungicides	EcoRic Biological Programme
Speed of action	Often relatively fast, particularly with curative/systemic products	Typically better positioned as part of preventive and ongoing biological protection
Preventive use	Effective when applied according to label and disease programme	Particularly relevant for preventive programmes and continuous biological support
High disease pressure	Often necessary for rapid intervention	May need to be combined with targeted chemical intervention
Low disease pressure	Effective but may represent unnecessary chemical intensity in some programmes	Strong opportunity for biological-first management
Resistance-management role	Requires careful FRAC rotation and mode-of-action management	Can diversify the overall protection programme and reduce exclusive dependence on single-site chemistry
Residue considerations	Must follow product label, PHI, MRL and export-market requirements	Biological approaches may help reduce dependence on conventional pesticide applications
Application frequency	Product and disease dependent	Programme and crop dependent
Cost per hectare	Highly variable depending on chemistry, frequency and crop	Should be evaluated against chemical applications reduced or avoided and crop performance
Soil / microbiome interaction	Product dependent	Biological activity is an integral part of the programme
Integration into IPM	Important component	Important complementary component
Emergency disease control	Often the stronger tool	Not normally the only tool to rely on during severe established infection
Long-term programme objective	Disease suppression/control	Disease suppression + biological support + reduced chemical dependence where practical

The conclusion is therefore not: Biological = good; chemical = bad

The more useful conclusion is: Each tool has a different role

 

When Should Farmers Use Biological Protection?

Biological crop protection is especially attractive when disease pressure is still low or when the objective is prevention. This is where many farms make a strategic mistake. They wait until visible disease is already spreading rapidly before introducing biological products.

A biological programme usually makes more sense before the crop reaches crisis level.

This allows beneficial microorganisms and the wider biological programme to become part of routine crop management rather than being treated as an emergency rescue treatment.

 

Scenario 1: Low Disease Pressure

Recommended strategy: Biological programme + monitoring + good agronomy

Imagine a coffee farm with:

• healthy new foliage;
• low visible incidence of leaf rust;
• normal rainfall;
• no rapid disease expansion;
• good canopy management.

Or a flower farm where Botrytis pressure is currently limited because humidity is being controlled and sanitation is strong. This is an ideal situation for a biological-first approach.

The farm can focus on:

• EcoRic biological protection;
• regular scouting;
• removal of infected plant material;
• canopy management;
• irrigation management;
• sanitation;
• nutrition;
• monitoring weather conditions.

The objective is to maintain the crop below the point where intensive chemical intervention becomes necessary.

This is one of the strongest potential economic roles of biological crop protection: preventing a low-pressure situation from becoming a high-cost disease outbreak.

 

Scenario 2: Moderate Disease Pressure

Disease symptoms are visible and increasing, but the situation is still under control.

Recommended strategy: EcoRic + targeted chemical treatment + IPM

At this stage, rejecting all chemical treatment simply because a farm wants to “go biological” may be commercially risky. Instead, a farm can use targeted fungicides where necessary while integrating biological protection into the overall programme.

The strategy might include:

1. identify the disease correctly;
2. assess severity;
3. identify the fungicide mode of action;
4. avoid unnecessary repetition of the same FRAC group;
5. use a targeted treatment;
6. return to or integrate EcoRic into the preventive programme;
7. continue monitoring.

This reduces the temptation to treat every spray cycle with the same chemistry. It also allows the biological programme to become part of resistance-management planning.

 

Scenario 3: High Disease Pressure

The crop is already experiencing rapid disease development.

Examples might include:

• widespread coffee leaf rust;
• severe tea blister blight during favourable weather;
• rapidly spreading Botrytis in flowers;
• a major foliar disease outbreak in vegetables.

Recommended strategy:

Chemical intervention first + EcoRic incorporated into the subsequent preventive programme

This is where professional advice is particularly important. A severe outbreak may require a registered, properly selected chemical fungicide capable of quickly reducing disease pressure. After stabilising the situation, the farm can reconsider the programme.

Instead of returning automatically to repeated high-intensity chemical spraying, management can introduce biological protection as part of the subsequent preventive cycle.

The programme then becomes:

Control the outbreak → reduce pathogen pressure → integrate biological protection → monitor → intervene chemically only when justified.

This is a considerably stronger agricultural strategy than pretending that biological treatment must replace every chemical intervention under every condition.

 

Coffee: Managing Leaf Rust More Strategically

Coffee leaf rust is one of the most commercially important diseases facing coffee producers. The business risk is not limited to visible leaf damage. Loss of healthy foliage can affect the plant's photosynthetic capacity, berry development and longer-term productivity. A conventional approach may rely heavily on repeated fungicide applications.

An integrated programme asks additional questions:

• What is the current disease incidence?
• Is the farm applying the same mode of action repeatedly?
• Can spray intervals be optimised?
• Can biological protection be introduced during lower-pressure periods?
• Are canopy density and humidity increasing disease risk?
• Is plant nutrition supporting healthy foliage?
• Can chemical intervention be limited to periods of real need?

Complex Food Agro conducted an EcoRic coffee demonstration in Cheborgei, Kericho County, between June and August 2026. During the demonstration, EcoRic-treated rows received three biological applications and were, according to farm records, excluded from the farm's chemical fungicide treatments during the trial period. By the final assessment, the treated rows showed greener, more uniform foliage and fewer visible rust-like lesions compared with their starting condition and the photographed conventional reference area.

Importantly, Complex Food Agro also recognised that further trials should include quantitative disease-incidence scoring, matched treatment blocks, rainfall measurements, yield assessment and exact cost-per-hectare comparisons. This is exactly how biological programmes should be evaluated commercially: not simply by whether the crop looks better, but by disease control, yield, quality and cost.

 

Tea: Blister Blight and the Importance of Prevention

Tea presents a different challenge because harvesting is continuous and the productive canopy must be protected consistently. Diseases such as blister blight can become particularly problematic when environmental conditions favour infection. In such systems, preventive crop protection becomes extremely important.

A strong IPM programme may include:

• field monitoring;
• canopy management;
• proper harvesting practices;
• sanitation;
• weather awareness;
• appropriate nutrition;
• biological protection;
• targeted fungicide applications when disease pressure justifies them.

The commercial goal is not to maximise the number of fungicide sprays. It is to maintain a productive plucking table at the lowest sustainable disease-management cost. For large tea estates, even a modest reduction in unnecessary chemical applications can become financially significant when calculated across hundreds or thousands of hectares.

 

Flowers: Why Botrytis Requires an Integrated Strategy

For Kenyan flower exporters, fungal disease has another major consequence: quality rejection. A flower stem may be harvested successfully but still lose commercial value if fungal damage develops before export, during transport or later in the supply chain. Botrytis is therefore not simply a field disease. It is a quality-management and post-harvest risk.

High humidity, dense canopies, wet foliage and infected plant material can contribute to disease pressure. This means fungicides alone cannot solve every part of the problem.

A stronger programme combines:

• greenhouse humidity management;
• ventilation;
• removal of infected material;
• sanitation;
• irrigation timing;
• canopy management;
• cold-chain discipline;
• biological protection;
• targeted chemistry.

For export flower farms, the key KPI should therefore not simply be: fungicide cost per hectare.

It should include: fungicide cost + biological programme cost + rejected stems + export-grade percentage.

Reducing a fungicide bill while increasing rejected stems would clearly not make commercial sense. Conversely, a slightly more sophisticated IPM programme that improves exportable yield could create substantial value.

 

Vegetables: Avoiding the “Spray Calendar” Trap

Vegetable growers often operate under intense disease pressure because of:

• short crop cycles;
• dense planting;
• irrigation;
• rapid canopy development;
• favourable temperatures;
• frequent cropping of the same or related species.

This can encourage calendar-based spraying.

For example:

Monday = fungicide.
Next Monday = fungicide.
Following Monday = fungicide again.

But calendar spraying can create unnecessary cost if applications are not based on actual risk.

A better system combines:

• scouting;
• weather;
• crop stage;
• disease history;
• resistant varieties where available;
• crop rotation;
• sanitation;
• biological protection;
• chemical intervention according to actual disease pressure.

FAO describes IPM as the careful integration of available pest-management techniques, including biological, chemical, physical and crop-specific approaches, with the objective of growing healthy crops while minimising unnecessary pesticide risks. This philosophy is especially relevant for intensive vegetable production.

 

Why Repeating the Same Fungicide Is a Long-Term Risk

Professional fungicide management requires more than changing brand names. Two products with different commercial names may still have the same mode of action. FRAC groups fungicides according to their biochemical mode of action precisely because fungicides within the same group may face cross-resistance.

FRAC therefore recommends that farmers and crop-protection professionals understand the FRAC code shown on product labels and design programmes accordingly.

For example, simply rotating:

Brand A → Brand B → Brand C

does not necessarily constitute true resistance management. If all three use the same mode of action, selection pressure may remain similar.

The more meaningful programme is: different effective modes of action + biological protection + cultural practices + disease monitoring.

 

EcoRic as Part of Resistance Management

Biological products can add another layer to the protection programme. The key advantage is not that biological products somehow make resistance impossible. Rather, they can help reduce exclusive dependence on repeated applications of the same chemical mode of action.

This can be commercially valuable in crops where farmers may otherwise make multiple fungicide applications throughout a season.

The potential strategy is:

Traditional programme

Chemical A
→ Chemical A
→ Chemical B
→ Chemical A
→ Chemical B

versus: Integrated programme

EcoRic biological protection
→ monitoring
→ targeted Chemical A if required
→ EcoRic / biological programme
→ Chemical B when disease pressure and resistance strategy justify it
→ biological protection

The second system should not be followed mechanically.

The actual programme must depend on:

• crop;
• pathogen;
• weather;
• disease severity;
• registered products;
• resistance risk;
• farm history.

But the principle is important: every avoided unnecessary chemical application reduces both direct cost and selection pressure.

 

What About Residues and Export Crops?

Residue management is particularly important for Kenyan farms supplying export markets.

Producers must comply with:

• registered use patterns;
• label rates;
• pre-harvest intervals;
• maximum residue limits applicable to destination markets;
• buyer-specific standards.

This is especially relevant for:

• vegetables;
• herbs;
• fruits;
• flowers where buyer sustainability programmes apply.

Biological crop protection may help farms reduce dependence on conventional fungicides where agronomically appropriate. However, biological products should not be marketed as a reason to ignore conventional disease intervention when crop loss is imminent.

The correct objective is: achieve reliable disease control with the lowest necessary chemical intensity.

Which Programme Is Cheaper?

This question cannot be answered simply by comparing the price of one litre of chemical fungicide with one litre of EcoRic.

The correct comparison is: Total disease-management cost per hectare.

For example:

Programme A - Conventional

8 chemical fungicide applications

Cost per application:

KES 4,000/ha

Total:

KES 32,000/ha

Programme B - Integrated

4 biological applications:

KES 2,500 × 4 = KES 10,000

plus

4 targeted chemical applications:

KES 4,000 × 4 = KES 16,000

Total:

KES 26,000/ha

Potential programme difference:

KES 6,000/ha

Across 100 hectares:

KES 600,000

This example is illustrative only.

Actual savings depend on:

• EcoRic dosage;
• chemical fungicide selected;
• spray frequency;
• labour;
• machinery;
• disease pressure;
• crop value;
• yield;
• quality.

But there is another important financial variable.

If the integrated programme helps preserve fungicide effectiveness, improve marketable quality or reduce crop rejection, its economic value may be much greater than the direct difference in spray cost.

 

Do Not Calculate Cost per Spray Only

A cheap spray can become very expensive if disease control fails. For that reason, farms should evaluate:

Cost per hectare

but also:

Cost per tonne produced

Cost per kilogram of export-grade produce

Cost per 1,000 marketable flower stems

Crop rejection percentage

Number of chemical interventions per season

Yield protected

This gives management a much more accurate view of crop-protection economics.

 

A Practical Decision Framework

Farm managers can use the following simplified system.

LOW DISEASE PRESSURE

Primary strategy:

EcoRic biological programme

• monitoring
• cultural controls
• good crop nutrition

Objective: Prevent disease from reaching economically damaging levels.

MODERATE DISEASE PRESSURE

Primary strategy:

EcoRic

• targeted chemical fungicide
• FRAC rotation
• monitoring

Objective: Suppress developing disease without unnecessarily increasing chemical intensity.

HIGH DISEASE PRESSURE

Primary strategy:

Immediate appropriate chemical intervention

• removal of heavily infected material where practical
• disease-pressure reduction
• subsequent EcoRic preventive/IPM programme

Objective: Protect the crop first, then reduce the probability of returning to continuous intensive chemical treatment.

 

When Should You Not Reduce Chemical Fungicides?

Reducing chemistry simply to achieve a sustainability target is not good agronomy. A farm should be cautious about reducing fungicide intensity when:

• disease is spreading rapidly;
• environmental conditions are highly favourable to the pathogen;
• the crop is highly susceptible;
• the value of potential crop loss is very high;
• biological protection was introduced too late;
• disease monitoring is inadequate.

In these situations, immediate crop protection may have priority. Once disease pressure is stabilised, the programme can be redesigned.

 

Five Questions Every Farm Should Ask About Its Fungicide Programme

Before the next spray cycle, management should ask:

1. What disease are we actually controlling?

Do not spray simply because “fungicide day” has arrived.

2. What is the current disease pressure?

Low, moderate or high?

3. Which FRAC mode of action did we use previously?

Brand rotation is not always mode-of-action rotation.

4. Could biological protection be used during lower-pressure periods?

This may reduce unnecessary chemical dependence.

5. What is our true cost of disease management?

Include chemical products, biological products, application labour, crop loss and quality rejection.

 

How to Test EcoRic Without Taking Unnecessary Risk

Commercial farms do not need to change their entire fungicide programme immediately. A controlled demonstration is more useful.

For example:

Control Block

Existing conventional fungicide programme.

Integrated Block

EcoRic + targeted fungicide applications according to disease pressure.

Then measure:

• disease incidence before treatment;
• disease severity;
• number of chemical applications;
• EcoRic applications;
• chemical fungicide expenditure;
• biological programme expenditure;
• labour;
• yield;
• quality;
• crop rejection;
• final cost per marketable unit.

This provides management with actual farm data rather than marketing assumptions.

 

EcoRic Is Not About “No Chemicals”

The strongest future for biological crop protection is not based on telling farmers that all chemical agriculture is wrong. Modern commercial agriculture requires flexibility. There will be situations when chemical fungicides are the most appropriate tool. There will also be many situations where routine chemical applications can potentially be reduced, delayed or integrated with biological protection.

The objective should therefore be: Right product. Right timing. Right disease pressure. Right economics.

EcoRic can become one component of that decision-making system.

From Fungicide Programme to Disease-Management Programme

This change in terminology is important.

A fungicide programme asks: What will we spray next?

A disease-management programme asks: Why is disease developing, what is the current risk, and which combination of tools will control it most effectively?

That combination may include:

• crop genetics;
• sanitation;
• canopy management;
• nutrition;
• irrigation management;
• weather monitoring;
• biological crop protection;
• chemical fungicides;
• resistance management;
• field scouting.

This is the foundation of Integrated Pest Management. For Kenyan commercial agriculture, it also represents an opportunity to reduce unnecessary input expenditure while maintaining the disease control needed for profitable production.

 

The Commercial Objective

The purpose of integrating EcoRic should not be to demonstrate that a farm can use fewer chemicals simply for the sake of using fewer chemicals.

The commercial objectives should be measurable:

Maintain or improve disease control.

Protect yield.

Maintain or increase marketable quality.

Reduce unnecessary chemical applications.

Manage fungicide-resistance risk.

Reduce total disease-management cost where possible.

Protect profitability per hectare.

If these objectives are achieved, biological crop protection becomes not simply a sustainability initiative. It becomes a business strategy.

 

Is EcoRic Suitable for Your Current Fungicide Programme?

Every farm has a different disease-management system. A flower farm in Naivasha may have a completely different fungicide rotation from a coffee farm in Kericho. A tea estate managing blister blight has different requirements from a tomato producer managing multiple foliar diseases. For this reason, Complex Food Agro does not recommend a universal replacement schedule. Instead, the first step should be to understand your existing programme.

Not sure whether EcoRic can be integrated with your current fungicide programme?

Send us your spray programme and crop - our agronomy team will review it.

Please provide:

• Crop
• Farm location
• Farm size
• Main fungal diseases
• Current fungicides
• Active ingredients, if known
• FRAC codes, if available
• Application rates
• Application frequency
• Approximate fungicide cost per hectare
• Current disease pressure
• Any residue or export-market requirements

Complex Food Agro can use this information to develop a proposed EcoRic + chemical + IPM demonstration programme for evaluation on your farm. The objective is not to remove chemistry blindly. It is to identify where biological protection may help your farm achieve more sustainable, resistance-aware and economically efficient disease management.