The crucial role of flowering in macadamia yield forecasting.

Interview with Experienced Maclands grower: Daron Naidoo, Operations Director, Eastern Produce Malawi (EPM)

Flowering is the first and most important natural step in macadamia production. However, what exactly does it mean for the crop, and why is it so critical to forecasting yields? To shed light on this crucial phase, we spoke with Daron Naidoo, Operations Director at EPM, who, with over 25 years’ experience working in agriculture, the last 5 years with Macadamia, is one of our seasoned growers. Here, we discuss what we look for during the flowering season, how we manage risks, and why flowering is the key to everything that follows.

Why is flowering important?

When you think about the health of a macadamia orchard, flowering seems like a relatively small event in the grand scheme of things, but as Daron explains, it’s actually the key starting point for determining the success of that season’s harvest because it is the start of the reproductive phase of the plant.

“Imagine walking through a macadamia orchard in Malawi in July, where the trees are covered in delicate white  blossoms – a scene jokingly referred to as “Christmas in July”. But this display isn’t just beautiful to look at, it’s the first, essential step in predicting the size of the harvest to come.”

As the Australian Macadamia Growers Handbook, notes “potential yield is determined by the number of flowers produced, effective pollination and retention of pollinated nuts.  Any event that interferes with these processes may influence yield.”  Flowering is essentially the precursor to crop and yield.  A good flowering initiates the potential for a good harvest.  A poor flowering restricts the ultimate harvest potential.

What do we look for during flowering?

So what does ideal flowering look like, and how can we tell if things are going well? Let’s take a look at the key parameters and warning signs.

Daron: “We’re really looking for intense and widespread flowering across all trees, cultivars and orchards. The more flowers we have, the better the chances for pollination, nut-set and yield. We also monitor flowering in overlapping generations.  A staggered flowering over several generations reduces our risk of crop loss due to sudden adverse weather events, like the extreme hot, dry spells we sometimes face later in the season. If the flowers and developing nuts are spread across different stages, a single weather event won’t spell total disaster, and the risk of losing everything at once is somewhat mitigated.

For example, this year we have seen two to three flower generations across all five EPM Estates.  Two of our Estates had an early flowering in April-May this year, and those nuts are currently at the hard-shell phase – these nuts are now through their most vulnerable stage of development, and are more likely to carry through to maturity.  Our other three Estates had relatively late but still extremely heavy flowering in July and August into September.  August through September saw our greatest flowering of the season, which was unusually late.”

Daron explains that late and uniform flowering in August or September may seem promising at first, but can signal a hidden vulnerability in Malawi’s macadamia orchards. The nuts formed during this time are exposed to the country’s harshest weather conditions in October and November, high heat combined with erratic rainfall, just as they’re reaching a critical stage of development. This climatic stress can result in poor nut formation or complete crop failure, even when flowering appears prolific.

In some cases, farmers witness a dramatic burst of blossoms yet find little to no yield at harvest. One theory is that macadamia trees naturally produce an overwhelming number of flowers, of which only around 3% mature into nuts. A biological strategy that may be efficient for survival but frustratingly inefficient for cultivation.

“In addition to monitoring the intensity of flowering at each estate, other factors are measured, which also indicate potential yield. These include flower coverage, flowering stages such as advanced bud and anthesis, pollination – bee activity, nut-set and nuts per raceme (cluster). All these factors come together to give a clearer picture of not only the expected yield but also the health of the orchards.  Longer flower racemes are considered a strong sign of a healthy orchard. Thanks to our improved precision agriculture nutritional regime, and our regenerative agriculture interventions, we’ve observed improved flower coverage and longer flower racemes in recent years.”

How flowering helps us with the yield forecast

One of the most important aspects of flowering is its role in forecasting. We wanted to know how flowering ties into overall yield predictions, so we asked Daron to explain."

“While flowering marks the starting point of the macadamia crop cycle, it is only the precursor to the following stages of crop production. Macadamia is a reproductive crop, and flowers serve not just as yield predictors but as biological signals designed to attract pollinators. Their colour, scent, and nectar are invitations to insects such as bees, who get to work transferring pollen, triggering successful pollination. It's this process, not just the abundance of flowering, that determines fruit set and eventual yield. Without active and effective pollination, even a spectacular flowering phase can result in minimal crop development. So the real story begins not just with the flowers themselves, but with the ecological partnership they form with their pollinators.”

How we manage risk from adverse weather

Of course, weather plays a big role in flowering, and we can’t always predict it. Daron discusses how we manage the uncertainties caused by climate, and climate change.

“In regions like Malawi, weather events, especially during the flowering and early nut development stages, are critical. We hope to have several staggered flower generations to spread the risk. If one generation of flowers is detrimentally impacted by an adverse weather event, say a heatwave or very strong winds, the others might still survive. It's all about  spreading that risk.”

Maclands is unique in its trans-African platform covering Malawi, South Africa and Kenya. Growing macadamia across these three regions reduces risk by allowing us to balance crop production; if adverse weather affects one location, we can supplement with harvests from another. Growing macadamia across these three geographically diverse regions not only helps manage weather-related risks but also enables Maclands to bring its harvest to market earlier, and over a longer time frame.

Flowering might appear to be a straightforward phenological phase, but as Daron pointed out, it's the pivotal starting point of reproduction. No flowers means no pollination, and without pollination, there are no macadamias. That’s why we closely monitor flowering and ensure we understand its role in the growing cycle. By doing so, we can better anticipate and plan for harvest, provide optimal conditions, keep the bees active, and set the stage for nature to perform at its best. This depth of expertise from our dedicated teams enables us to consistently deliver excellent quality macadamias, season after season.

Now in September, Malawi’s flowering season is coming to an end, and the Maclands team is keeping a close eye on progress, eagerly tracking signs of nut set and the next stages of development. Stay tuned for more expert conversations with the Maclands team as we follow the journey from flower to harvest.