Coffee resilience: how PNG’s farmers are leading the way in sustainable coffee production

A 6-year ACIAR-supported project has helped many smallholder coffee farmers and their families in the highlands of Papua New Guinea (PNG) improve their livelihoods by targeting key factors impairing coffee production.

Helping farmers improve the quality of their beans, and connecting them with buyers willing to pay a premium for quality, has boosted their incomes. The project has also engaged women more actively in coffee farming by integrating vegetable crops with coffee plantations, allowing the women to earn their own incomes.

Improved harvest quality

Professor George Curry from Curtin University in Western Australia led the ACIAR-supported project, working with partners at CSIRO and the Coffee Industry Corporation in PNG. The initial focus of the project was to improve the quality and consistency of the coffee beans being produced. Traditional coffee harvesting and processing requires very specific practices to produce high-quality coffee. But several decades of economic instability and the closure of rural mills and processors had led to a decline in coffee farming knowledge within PNG smallholder communities.

‘The harvesting and processing practices were not conducive to good-quality coffee. It was inconsistent and affected the flavour,’ said Professor Curry.

‘With the rise of roadside buyers and no direct link between farmers and exporters in town, farmers weren’t getting a price signal for quality. Whatever quality coffee they produced, they just got the same basic low price, so there wasn’t an incentive in trying to improve quality.’

The project team worked with farmers to trial a demucilager (a mini wet mill with a pulper) that automatically removes skins, pulp and mucilage from the coffee cherries, leaving coffee beans that are ready for drying. The coffee it produced was of a consistently high standard.

Man pouring coffee berries into a machine. — Using an automated demucilager to remove skins and pulp from coffee cherries has helped growers to harvest beans more efficiently. Photo: Curtin University

‘With this machine that we now have, it gives good-quality coffee. We do [less] work, and we see big fruits from it,’ says Mr Blacky Buka, a coffee farmer working with ACIAR.

Professor Curry’s team also linked farmers with an exporter who agreed to buy the crop with payments based on quality. Farmers earned up to $10.30 kina per kg (approximately A$4), an increase of up to 77% on previous prices.

Farming practices

The project also trialled different farming systems to lift the productivity of coffee plantations without necessarily increasing the intensity of farming or the farm inputs required.

‘Smallholders operate quite differently from large-scale farmers,’ said Professor Curry.

‘The assumption is that extension has to take farmers from low-input systems of production to high-input, high-yield, capital-intensive systems. But the low-input system of production accommodates a “way of life” that is highly valued by farmers in PNG.’

Implementing long-lasting and effective changes in these communities has meant challenging the traditional top-down extension approach and building on a basis of techniques that PNG growers have employed for years.

A woman and man pouring coffee berries into a machine.

Coffee farmers use a hand-operated demucilager that removes skins and pulp from coffee cherries, leaving beans ready for drying. Photo: Curtin University

Two men standing next to a raised garden bed.

Pulp from the coffee cherries is used as fertiliser to produce other crops. Photo: Curtin University

Coffee cherries are floated to assess quality before the beans are extracted. Photo: Curtin University

Man carrying a bag walking down a hill path

A smallholder coffee farmer carries beans to market. Photo: Curtin University

Engaging female farmers

One method the project employed was intercropping – growing vegetables within the coffee crops to gain extra value from the land. This has provided the communities with an additional source of food and income, and also empowered women in the communities to be more involved in coffee production.

Women weren’t getting the return for their labour because coffee was a crop managed by men. So, we tried intercropping coffee with cabbages, which would be an additional income source for women.

Professor George Curry
Curtin University

This gave women a way to independently profit from coffee farming and had considerable benefits for the coffee production itself.

‘People were going into the coffee gardens more often, so they were able to monitor the pest and disease situation and potentially control outbreaks before they became too serious. They also controlled the weeds because they don’t want the weeds around the cabbages, and if they applied fertiliser to the cabbages that benefited the coffee as well,’ said Professor Curry.

Other techniques the project tried included promoting correct shade levels using nitrogen-fixing shade trees such as Casuarina within the coffee gardens. The appropriate shade levels can protect coffee trees from extreme weather. Nutrients brought up from deep in the soil are made available to coffee trees through leaf litter, which also provides mulch that reduces soil erosion, maintains soil moisture and suppresses weeds.

Suppressing plant pests

The project recommended that coffee be planted in lower densities and with tall varieties, making for easier harvesting. This lower-density farming has the additional benefit of making it easier for farmers to undertake coffee garden sanitation to suppress coffee berry borer (CBB). CBB was first found in PNG in 2017 and, while it is not yet present in Australia, it represents a significant biosecurity threat. Working with smallholder coffee farmers in PNG to improve sanitation and reduce potential infestations could help prevent incursions of this destructive pest in Australia.

Professor Curry’s team has worked closely with a complementary ACIAR-supported project investigating CBB. This was led by entomologist Dr Ian Newton from the Queensland Department of Primary Industries, in conjunction with entomologists from PNG’s Coffee Industry Corporation. This project found that fortnightly harvesting of coffee cherries would break the reproductive cycle of CBB.

Insects on a bunch of coffee cherries — ACIAR-supported research is helping to control coffee berry borer, seen here on coffee cherries. Photo: Curtin University

Tailored training

Designing an agricultural system that worked with what PNG farmers already knew and did well resulted in higher biodiversity, greater resistance to pests and disease, and more community resources like medicinal plants and firewood, all at a comparatively low labour input.

The methods this project developed have been documented in a training package called ‘Smallholder coffee production in Papua New Guinea’. The methods are designed for low-input production systems and could be adapted for countries with similar sociocultural contexts as PNG, such as Timor-Leste.

While the project wrapped up in 2024, Pastor Albert Ukaiya, spokesperson and leader for the SK2 Linupa Farmers Cooperative Limited, said the ACIAR-supported work is helping coffee-growing communities to thrive.

‘Our thoughts were that we must stand on our legs with what we already have to improve our living. When they were doing the research work, the research supported [our] ideas,’ said Pastor Ukaiya.

‘The research made visible the difficulties we had. It was also looking at ways to address our difficulties. Now we have short-term, medium-term and long-term plans, we are not confused. We will build a strong foundation for our children to be financially independent, and they will develop our place.’

ACIAR Project: ‘Improving livelihoods of smallholder coffee communities in Papua New Guinea’ (FR2024-028)