Kia ora, welcome to our Avocado Quarterly Newsletter

eNews Avocado 1st Quarter 2022

Brien James

As avocado growers, we are coming to the end of a trying season, and at times it has been easy to feel despondent. But when we see and hear what is happening to the people of Ukraine at the hands of Putin, our worries are nothing in comparison.

However, as it’s the end of a season and another is about to start, it’s a good time to reflect on how well the industry is serving us. Here are a few things I’ve been thinking about.

Maybe it takes a year with poor returns to highlight the fact that what we, as growers, need from our exporter is regular detailed written information about our likely returns for the season. This is vital information to enable us to plan how we manage the orchard’s financial affairs during difficult times. It is important that all growers receive this information, otherwise rumours and best guesses take on too much significance.

Labour is fast becoming an industry issue. I can speak from personal experience from this season, when labour shortage was the primary reason the final pick on my orchard wasn’t completed before cyclone Dovi struck. I am still trying to harvest the fruit that is left, but I will have to hope prices lift so returns are bigger than the picking bill.  How do we attract and hold sufficient pickers so we have them when we need them throughout the season? Do we need to offer loyalty schemes? Or is it through guaranteeing staff job security beyond the picking season?

Another thing to consider is how much nitrogen you use on your orchard. AVOCO, after reviewing industry literature, is recommending we reduce nitrogen usage because they believe it seems to be impacting negatively on fruit quality. Others in the industry recommend the use of nitrogen because it helps to sustain higher production. And of course, there are environmental ramifications as well.  Is this another dilemma for us to face?

There is always something to think about while I’m on the tractor or mower. Meanwhile, I hope you get to enjoy some autumn leisure time.

Brien James

Daniel Birnie
Avocado Manager

Operations Update

Below is a summary of the top performing orchards by tonnes per hectare, export packout and average size.

We will refresh this report at the conclusion of all our packing (as we generate our comparative reports) and publish any changes.

Well done to the growers below. Of interest, three of the top four yielding orchards all came from the same road, Gridley Rd in Rangiuru.


Orchard nameGeographic Area
David and Rosalie AngellRangiuru43.4
Matthew Bradford and Gloria GilbertPukehina37.6
Lee Crawshaw and Bridget MaherRangiuru37.3
Robbie and Julene MooreRangiuru36.8
Roger and Kerry CrotonMatapihi36.7
Ian Conway and Julie ManaghPaengaroa84.80%
Alister and Carol NivenKatkikati South83.50%
Joan MayTe Puke No 1 – No 283.30%
Keith and Caroline BoylePaengaroa82.10%
Daryl Pratt and Virginia FlausKatikati North82.00%
Tim Shaw and Rebecca AllenAthenree20.6
Mike BushettPaengaroa20.6
Daryl Pratt and Virginia FlausKatikati North20.7
Janice FlemingOpotiki20.7
Stan HoppingTe Puke No 1 – No 220.9

Katherine Bell
Grower Liaison Representative

Due to an ongoing need indicated from growers for technical support, the avocado team at Trevelyan’s has decided to hold a series of regional workshops and discussion groups of up to 20 people. These small groups give growers the time to interact with our team and opportunity to talk about the issues they are facing on their orchards.

During recent discussion groups the team covered the topic of medium density pruning.  The feedback following these has been positive, with growers asking for further workshops to be held. Our next round of discussion groups will discuss thrip control and with a high level of demand on this topic expected, we will host as many workshops as required to ensure no grower misses out.

The team have further workshops planned over the next few months covering the following topic areas:

Financial Sustainability

  • Planning
  • Prioritising inputs and budgeting
  • Long-term financial viability


  • Key factors
  • Soil and leaf testing
  • Nitrogen as the key manipulator element


  • Lifecycle
  • Integrated control – The Pegg Wheel
  • The importance of timing

To register your interest for the above topics, or if you have any topics you think are important or challenging that we should talk about, please contact your Grower Representative. We also would like to hear from you if you would like to host one of these discussion groups on your orchard.

We look forward to seeing you soon.













Jonathan Cutting discussing medium density pruning with growers’ during a recent workshop.


Jonathan Cutting
Avocado Technical Manager

Avocado Fruit Quality

What is fruit quality?  Growers have been exposed to “fruit quality” conversations a great deal over the past few years.  More recently, we have seen the introduction of an AVANZA exclusion list, based on quality outturns in market.  We hear reports of indifferent fruit quality from Asia.  As an industry, we even have an export “Quality Manual” developed over more than 25 years and much of it based around compliance.

“Fruit quality” means different things to different people depending upon where they are in the avocado value chain.  For example, a consumer may think of quality as relating to internal eating quality and shelf life, while a commercial ripener may think of quality as checker boarding (uneven colour or fruit firmness in a tray).  Quality to a grower may be blemish and superficial grading defects.  Nobody is wrong, but it depends on where the financial or performance drivers are for you!

New Zealand avocados have a long value chain and everyone in the chain plays a part in delivering quality.  But, in reality, it is only growers that can improve fruit quality!  This is because fruit quality is determined at the point of harvest.  Thereafter, all those involved in the value chain can only try to reduce, preferably minimise, quality loss as the fruit moves from the orchard to the final consumer.  And we are dealing with a fruit that does not have a long shelf life – somewhere around 30 days.  We are also dealing with size picking and a very long harvest season – so picking at optimum maturity is not an option.  When we understand what exactly quality is, and where it is improved or lost, only then we can realistically look at the quality improvements we need to ensure viable financial success in the future.

This general look at fruit quality focuses on the grower impact on fruit quality.  Others play an important part in fruit quality but it all begins with the grower – and they take all the financial risk!  I do believe that the better the inherent quality potential at harvest, the better for all.  Hopefully, all things being equal, and the value chain working properly, the “best quality fruit at harvest should always be the best fruit on the consumer’s table”.


Growers “grow” the fruit.  They get choice around the inputs and systems they wish to use to grow the crop.  They are also the only part of the value chain that can alter or “improve” fruit quality.  Growers have two primary strategies to address this:

  • Grow “robust” fruit using established horticultural principles including good tree health, optimised mineral nutrition, balanced vigour and reduction of disease or stress
  • Minimise the impact of insect blemish or pathological infection

There is not much good avocado information on growing “robust” fruit.  There is a good reason for this in that most of the research effort over the past 60 years has been focussed on:

  • Phytophthora root rot
  • Low yields (globally the avocado is considered a low yielding crop when compared to other fruit tree crops)
  • Alternate and or irregular bearing

We can safely assume that, at least in the short term, there will be no genetic solution as Hass is well established as the global trading standard.  Most of the root stock breeding and selection work is still focussed on root rot.

  • Calcium nutrition. Most of the peer reviewed published literature in avocado focusses on the Fuerte and Pinkerton cultivars.  This research explores the role of calcium affecting physiological long-term storage disorders such as grey pulp or flesh brown mediated by the polyphenol oxidase enzyme complex.  The literature is awash with calcium involvement in physiological disorders in other crops such as apple, mango, tomatoes, broccoli and lettuce to name a few.  Unfortunately, I could find very little on possible relationships between pathology and calcium in avocado.  There is some literature exploring a role for silicon in reducing pathology.  However, it is prudent to assume that a relationship between avocado fruit calcium and fruit fungal infections exists, even if weak, until proven otherwise.  Calcium uptake in the avocado is poor.  Only non-suberised white root tips take up calcium.  Active uptake of calcium by roots is minimal and most calcium is taken up in the mass flow of water from roots to leaves.  Maintaining good root health is key to calcium uptake.  There is no obvious downside to improving calcium nutrition other than cost.
  • Nitrogen nutrition. This is a controversial and ambiguous topic.  In New Zealand, we address autumn and winter leaf photo oxidation and low temperature chlorophyll repair with nitrogen targeting leaf nitrogen in the 2.6-2.9% N range.  Some growers, especially on sandy soils, push yield using nitrogen.  On the flip side, high nitrogen leads to excessive vegetative growth, shading of good flowering wood and more pruning or earlier tree thinning.  There is also the impact of high nitrogen on fruit quality.  Again, most of the peer reviewed avocado literature is correlation work or speculative for a biochemical/ physiological role for nitrogen in lower fruit quality in Hass avocado.  However, again it is prudent to assume that a relationship between nitrogen inputs and fruit quality exists, until proven otherwise.

The regulators, via the RMA, are moving to control the amount of nitrogen that can be applied annually.  At Trevelyan’s we are trying to respond to and balance multiple and often conflicting nitrogen drivers.   We are trying to keep annual nitrogen applications to between 90 and 130 units of N annually per ha.  However, some growers are pushing back claiming that their orchards and yield are suffering.  We are reviewing and monitoring the situation carefully and tweaking our fertiliser recommendations where appropriate.

  • Pruning and open canopies. There is scientific evidence that open canopies, deadwood removal and “mummy” elimination reduce the pathological fungal inoculum loading on fruit, resulting in fewer latent infection sites. As pruning and “opening up” trees is now an established practise on many orchards, we see this as assisting “fruit quality”.  Regular pruning of water shoots should dramatically reduce the amount of deadwood in the canopy as the canopy remains better illuminated and more stable.  In terms of pruning, a “calm” flat canopy devoid of heavy wood is the holy grail.
  • Good nutrition. Growers are always encouraged to practise good nutrition.  What this really means, is harder to define.  This is a large topic on its own, so I am acknowledging this rather than getting into the detail.  Some key comments are:
    • target leaf norms are something to aim for
    • annual fertiliser programmes based on tree phenology are better than “knee jerk” reactionary inputs
    • the “little and often” approach has gained much traction in recent years.
    • There is an assumed role for boron in fruit quality due to its cellular differentiation role
  • Soil and irrigation. The horticultural principle that diseased or stressed trees are more likely to produce fruit that is prone to diseases and physiological disorders is widely accepted.  Growers can do the following:
    • Make sure that soils are well drained, well aerated and that nutrients are in the pH band for maximum availability (pH 6.1-6.4)
    • Monitor soil moisture and apply irrigation when trees become moisture limited
    • Apply mulches and protect the root system
  • Preventative copper sprays. Spraying copper has been shown to reduce rots in fruit.  However, it is not a panacea and the current recommendation to apply eight coppers annually is blunt.  Additionally, the real benefits of copper are quite small as a percentage improvement with large standard error deviations and in some cases too few copper applications can exacerbate the situation.  Therefore, some growers are shying away from copper applications.   We need much better guidelines on copper use (more akin to the kiwifruit industry) around:
    • Copper use in advance of big weather systems moving in
    • preharvest sprays application
    • properly understand our risk periods and target those periods
    • and try to add some new, non-copper based and more effective chemistry to reduce fungal loadings
  • Weather conditions around harvest. This is most likely a key driver.  It is also a frustration and slows down harvest.  Picking after rainfall is the only “Quality Manual” compliance/ best practise requirement for growers apart from Food Safety requirements.  The 5mm rainfall and 24 hours wait system is now 20 years old, and needs to become more precise and less general. Rainfall is a secondary measure, and is based on an assumed relationship between the amount of rainfall and lenticel turgidity.  It does not take variable influencers such as soil type, wind, heavy rainfall (more than 50 mm), irrigation and relative humidity into account.   It seems we need a direct measure that is site specific such as soil moisture, or better yet, a direct measure of lenticel turgidity.

In summary, we can see that “growing quality fruit” and the decisions around harvest are complex and interconnected.  There is no one single “silver bullet”.  Quality is further confounded in that every property is different and has its own challenges, differing risk profiles and opportunities.  We also don’t really have all the tools and knowledge (a blueprint) to deliver great quality every time.  What we do need is a tailored quality plan for each property and then to implement that plan. We need to agree that quality is a continuous input that never stops and that it is complex.  Everyone in the value chain has a part to play and when we hand over the “quality transfer and responsibility” to the next link in the value chain, we do so knowing that we have done our bit to the best of our ability.


Stuart Jennings
Avocado Orchard Manager

Orchard Management

The past few months have been busy with organising sprays in response to AvoGreen monitoring reports. We have been using pyrethrum products when spraying around kiwifruit or if we are still picking avocados, as it’s a short withholding period.   Alex from AvoGro has mentioned that Zetapy is a lot cheaper than Pyganic.

Other on orchard projects include fertilser applications and coming up through the autumn, injections are taking place for phytophthora control.

At Te Hua Whenua orchard (pictures below) an autumn planting has taken place by David Wills and his team.  These plants came from Riversun Nursery in Gisborne.  Te Hua Whenua is one of our managed orchard on Kairua Rd in Papamoa, and has around 1.5ha of mature orchard, 1.5ha at 3 years-old and another 3ha at 1-2 years-old.

Another part of our planning for the next few months is soil and left tests – we will be completing these on all our managed orchards through late April/early May, and we will also be looking at applying hortiprotect prior to any winter frosts.












Pic 1 – Te Hua Whenua orchard looking towards Mangatawa












Pic 2 – Te Hua Whenua orchard (2 year-old trees) with lids on

Zara Marra
Local Market Manager

Local Market Update

This season to date (1st June 2021 – March 2022) the domestic market has consumed 3.26m TE compared to 2.07m last season.  This is inclusive of 403k TE diverted into NZ from export volume.

As predicted, the season has been extremely challenging. The increased volume put downward pressure on returns.  Class 2 volumes were adequate for NZ consumption leaving Class 3 as surplus.  Most of the Class 3 was diverted to process.  At times these volumes were also problematic for the processors.  Retailers maintained multibuys to maintain the flow of volume and in return increased NZ consumption.

Export volumes packed for the NZ market finish at the end of March.  As this volume clears, we expect values to increase to a sustainable level, and maintain local market volume into the new season.

The graph below shows how returns have tracked this season against a few of the highest and lowest seasons (based on size 24 returns).



















Local Market Returns

Local market returns as below per 5.5kg tray

Due to the nature of the season we have been paying the Class 2 pools fortnightly, the Class 3 and processing will be paid once all funds have been received.






























Waste Not, Want Not

My grandmother was excellent at managing resources. Having grown up during the Great Depression and dealing with post-war rationing, she thought hard about what she really needed and never threw anything of value away.

When she passed away a couple of years ago, I inherited her sewing box. I spent some time sorting through it during the last lockdown. In today’s modern consumer society, it would be almost unthinkable to remove a zip or button from a used clothing item so it could be repurposed, or to unravel a woollen jersey to reuse the wool. Yet that is what my grandmother did.

What sustainability lessons can we learn from this frugal approach in the modern era of rampant inflation and supply chain limitations?

  1. Recognise that everything has value

When we buy something, there is a financial cost and an impact on the environment.  The use of resources also generates financial and environmental impacts. We can see this with the transport packaging used to export our kiwifruit around the world.

When an item is no longer required, we must dispose of it. Again, this has an environmental impact depending on where we land on the waste hierarchy (reuse, recycle, compost, landfill) as well as an associated cost. Our landfill costs at Trevelyan’s have gone from $200/tonne to $400/tonne in the last four years, so the choice of disposal route can have a significant impact. If we use less and waste less, then it will cost less and have less of an environmental impact.

  1. Look more closely at why and how you do things

The increasing financial and environmental impacts force us to think differently about how we work. One seemingly simple decision can lead to a cascade of impacts down the line. For example, the amount of fruit we condition check and repack means we produce a lot of packaging waste. We reuse as much as we can, but we still collected nearly six tonnes of polypropylene strapping for recycling in 2021.

The “Five Whys” is a simple technique which can help get to the root cause of an issue.  When a problem occurs, you drill down to its root cause by asking “why?” five times. Then, when a countermeasure becomes apparent, you follow it through to prevent the issue from recurring. This is particularly useful in the current COVID environment when circumstances are changing rapidly, and we need to adapt quickly.

  1. Take people with you on the journey

I am always inspired how our sustainability projects take on a life of their own, once we get the logistics ironed out. If we can help people understand the why of what they are doing, such as recycling, they feel empowered and are keen to help make a difference.  It’s amazing to see the sense of purpose that people get from doing something really worthwhile when they come to work.

  1. The best time to get started is now

There’s a popular Chinese proverb that says “the best time to plant a tree was 20 years ago. The second-best time is now.” And Desmond Tutu once wisely said “there is only one way to eat an elephant: a bite at a time.”  If we put these two ideas together then the best thing we can do is to start taking small steps, now.

When I get disheartened about how much work there is to do in the sustainability space, I reflect on what we have achieved at Trevelyan’s over the last few years. We have made huge strides in reducing our waste to landfill down to 8.84% in 2021 and we are getting more traction on minimising our carbon emissions. We have recently completed a project to relabel all our bins and I look forward to seeing the impact of this as we move through the season.













Frugal might be an old-fashioned word, but it’s certainly a valid approach in the challenging environment we find ourselves in this year, and as my grandmother would say… “waste not, want not.”

Grower Profile: Clark Family


Colleen and I had been dairy farming for 14 years when the opportunity arose to purchase eight hectares of land which we planted in kiwifruit. We developed this orchard in conjunction with milking cows and raising our three children. We had experienced the highs and lows of milking as well as growing kiwifruit, therefore in 1990 we bought eight further hectares and chose to diversify into avocados.

All four and a half hectares of planted avocados was a retirement project. We had heard how easy they were to grow, then just pick, so it seemed like a perfect lifestyle.

Very quickly reality set in and we discovered just how much work our 800 trees were. In 1994, with our trees looking very sick with an unknown diagnosed problem, we were fortunate enough to hear of Jonathon Cutting, who at the time was working at Massey with apples. As his background was with avocados and the industry screaming out for information on growing, he relocated to Tauranga and took us on as clients. He became our consultant from the first meeting, and we have had a wonderful working relationship with him ever since.

The family – Donna and Skugs, Robyn and Snow, and Andrew and Kelly – married and reproduced providing us with eight grandchildren and over the years they showed an interest in orcharding.

It gives us a lot of pleasure to work with our children and seeing their achievements.

Questions & answers as told to Jonathan Cutting

This is a multi-generational operation encompassing six properties and 20 ha of avocados now. How did this develop and what were the key drivers for all of the family involvement?

The family was looking at an opportunity for a passive income outside of their existing business interests. The reason we chose to develop another avocado orchard was because Roger and Colleen already had a successful avocado operation. There was an opportunity to plant on the back of the family dairy farm which was marginal dairy land and prime horticulture land. This is Paehua, our first orchard as a family operation.

How does your family make decisions and run the farms including new investments?

All meetings and discussions are held around the family dinner table over great food and a few drinks.  We are a family who all enjoy both of those things, as well as each other’s company.  The operation got too big to be run with our existing jobs, so Skugs was brought on as orchard manager.  Skugs was employed in 2020 to soak up all of Roger’s avocado knowledge and to take the load off the rest of the family members.

The early plantings are all orchards that were thinned out to large free-standing trees. That changed with Paehua, where the initial spacing is maintained and now the latest plantings are higher density. How did that happen and what was the thought process that drove this?  Knowing what you know now, what would you do differently?

Learning a lesson from Roger’s original orchard, planted back in 1992, where the trees got too tall to pick, we decided to manage tree height so we moved into a medium density planting at Paehua (7.5m x 7.5m) and then progressed onto high density planting in later orchards (8m x 4m).  In retrospect, we would manage the tree size earlier, even when there is a crop on.

Your operation is unusual in that you pick your own crop over the full length of the harvest season whereas most other growers use contractors with short picking periods.  What were the drivers for this decision and how do you see this approach going forward?

Due to our location, logistically we don’t have the luxury of contract picking gangs. Because of our picking regime, we can offer our own staff more regular work, with our own machines. However, this may not be sustainable in the future due to labour shortages.

We have just had what could be described as the worst season in three decades.  What are the key challenges that you as a family are debating right now regarding the future of your orchards and the avocado industry as a whole?

Our key challenge is having a consistent and reliable crop, as well as well-managed trees so the orchard can run efficiently and cost effectively.  We will be looking at simplifying our pruning system to make it more cost effective, and looking at other ways to save costs. We believe the industry needs to look at better incentives for producing good quality, good storing fruit and not subsidising marginal fruit.

What have you most enjoyed about the avocado industry during the past 10 years and what are the big issues your family and the industry face over the next 10 years?

Over the last 10 years we’ve enjoyed watching the growth of the orchard developments. This keeps the family connected.  It’s also great seeing the third generation of our family helping out, with the younger ones sowing fertiliser and weeding and the two eldest boys doing part-time picking in the Hydra ladders and other work.  Our biggest concern for the future is finding quality workers with the staff shortages country-wide.

Staff Profile: Laura Schultz – Grower Liaison

Tell us a bit about yourself and your background

I grew up in Te Puke, my family have kiwifruit and avocados so I couldn’t wait to get out of here after training vines as a teenager in the hot sun. I escaped to Auckland to study fashion, spent some time in Canada at the ski resorts and once I came home, I didn’t want to go back to an inside life so I found myself back on the orchard. This time I enjoyed it a lot more and fell in love with avocados. I have spent the past few years working on the orchard.

What attracted you to working at Trevelyan’s?

The people, getting to work with growers and the focus on sustainability.

What is your role and what does it involve?

My role is an avocado grower rep liaising between the packhouse and growers. This involves building relationships, sharing information and helping with everything from crop estimates to harvest.

When you’re not at work what do you like to do?

I like to be outside either on our avocado orchard or with my dog, doing something active like squash or hiking…or just enjoying a G&T in the sun.


Staff Profile: Nikki Aitken – Document Controller

Tell us a bit about yourself and your background

I have been working for Trevelyan’s since 2019.

What attracted you to working at Trevelyan’s?

Being part of locally-owned family business is a huge drawcard for me. I have a great team to work with in a fantastic environment, especially with today’s challenging times due to the pandemic.

What is your role and what does it involve?

Currently I have two roles with Trevelyan’s: Document Controller and most recently I was offered an opportunity to learn more within the industry as a qualified AvoGreen Pest Monitor which I really enjoy. It keeps me active and gets me out from behind my desk.

When you’re not at work what do you like to do?

I am very much an outdoors person, tramping and gardening and enjoy art & craft projects both for the garden and redecorating projects.