Written by Eric Cairnes, NZTCA – February 2000

So you’ve bought or are thinking of buying a rural block and perhaps earning some retirement income from growing something, preferably something you yourself like eating.  What about nuts? They are high value, store well, are eary to transport, lend themselves to niche marketing and can be managed on a fairly small scale.

Remember the in shell nuts you indulged in over Christmas.  If you chose well, you found some excellent quality locally grown walnuts or hazels.  Most of us however, bought mixed packs of nuts imported from around the world.  They were stale and rancid and we wondered why we had bought them.  Well perhaps its too cold for Brazil nuts here and peanuts are pretty marginal, but, almond, walnut, hazel, macadamia, pinenuts and chestnuts do well.  And how much better they would have tasted fresh.

The New Zealand Trees Crops Association, which has branches in most areas of the country, can help you get started, and most importantly, can put you in contact with other growers around NZ.  Information is willingly shared at field days and evening meetings and through fact sheets, because we recognise that this is the best way to learn more ourselves.

From time to time there are specialist nut seminars held, and the annual conferences (this year at Lincoln over Easter Weekend) nearly always feature field events and seminars given by experts on nuts.

So if you are serious about a commercial nut venture, you should do your homework.  Check out the world scene for indication as to potential.  (Get yearbook data and search the Internet).  Monitor trends in world prices, trends in planting and disease.  Does NZ offer a strategic advantage (eg. season, climate, disease, access to markets etc)?  What is the size of the local (ethnic) market?  What are the costs of growing and harvesting/processing the crop?  What supporting infrastructure is there to assist you?  Membership of NZTCA makes it easier to find answers for these and many other questions.

Decide how to market you crop.  Will you drop it on the local auction system, and accept commodity prices, or develop niche outlets for processed products and control the situation better.

In a general sense, the marketing aspect is the biggest hurdle for most small scale industries.  In NZTCA, many of us are green fingered growers, and not strong on the presentation/marketing end.  However, there are also many market success stories for niche products.

A new product in NZ such as gevuina nuts, may have difficulty establishing market demand unless there is sufficient supply.  Wholesalers or large retailers may not want to invest in promoting or stocking a product line unless quality and supply is secure.  Thus, even for products where there is established demand, but no local supply (eg pine nuts and pistachio), there is a ‘critical mass of product’ required to develop the market.  This amount is quite likely more than one or several growers could supply, so don’t try to capture the market on your own.  If you are keen on exporting, the amount of product to do business with may be orders of magnitude greater than would be necessary for domestic markets.  Our advice is to cooperate with other growers to develop the infrastructure and markets.

Thus one of the strategies of the newly formed Gevuina Action Group is to get as many trees as possible planted as soon as possible in order to be able to “launch the product”.  Quite deliberately, they are focussing on a few selections into order to standardise the product.  Naturally there are risks involved with new crops if the best selections are not yet known and market demand is uncertain.

In the case of macadamias, walnuts, chestnuts, and hazels, there is now an established demand for local produce (or for export) and some established infrastructure to harvest, process and market the produce.  The NZ Hazel industry is still very small, and gevuina, pistachio, almond, pecan, and pine nut are yet to gain ‘critical mass’ but gate sales and specialist retailers would still be interested in spot market sales.

The history of serious nut growing in NZ is quite recent and began with the foundation of the New Zealand Tree Crops association, 25 years ago.  Some of our early researchers were also on the staff at DSIR or MAF and no doubt this assisted with the professional approach and early successes.  A key trial area for nuts was the Crop research block at Lincoln and the cooperative venture with the then DSIR was a major success story.  Some of these trials continue in the grounds of Lincoln University under the auspices of Dr David McNeil, a Research and Development Coordinator for NZTCA.

Before the formation of NZTCA, no one had done any systematic selection or breeding of nut trees suitable for NZ conditions.  We weren’t even of the limitations of our climate.  How then to develop a nut industry?  The quickest way was not to spend 15 years breeding new varieties but to see how existing material would perform. The opinion was that NZ conditions were sufficiently different to other major nut producing countries, that imported varieties may not be any better than some selections already growing and adapted to NZ.

So in order to get the industries started, NZTCA held nut competitions to identify the best walnuts, chestnuts and hazels.  The best of these were then propagated and put into trial plantings and compared with the best overseas varieties.

In the case of walnuts, some local selections have done extremely well and four of these (Rex, Meyric, Dublin’s Glory and Stan) were given variety names in 1998.

Some of our local hazel selections (eg Whiteheart) also compare well against Italian and American varieties.

In the case of chestnut, due to the prevalence of chestnut blight in most other countries, there was reluctance to import any new overseas material.  Some did eventually get imported, but our local selections still form the bulk of the plantings.

With the founding of NZTCA, it still took 15 – 20 years of development to get walnuts, chestnuts and hazels to an industry size.
The nut crop summary below – WalnutChestnut

Walnut Chart

Species: Juglans regia commonly known as European, English or Persian walnut.

Recommended VarietiesNumerous seedling and grafted selections available. It is important to match the orchard site with the right variety. Research is still continuing to select the best varieties for North Is conditions.
ClimateRain or high humidity during spring to late summer increases the incidence of blight. Some varieties are more susceptible to blight than others. Dry east coast climates are preferred.

The leaves and flowers are damaged by unseasonal frosts. Areas subject to frost after mid October may benefit from late leafing varieties.

SoilCritical. Must be free draining down to 2 metres. Fertile soils of moderately high pH are required. Nutrients need to be well balanced.
MarketsPresent local consumption far exceeds local supply and quality NZ kernel is readily sold. Said to one of the few commodity products which has maintained its value over the years.

The (heart) timber is amongst the most valuable wood there is, provided it is well grown and trees of large size. Walnut burr is particularly sort after. Heart content varies greatly.

HarvestingThe nuts fall to the ground and must be harvested within a day to avoid deterioration. Various machines (vacuum and hedgehogs) available to pick up nuts. In dry climates, daily collection is less critical.
Post-HarvestNuts should be cleaned by water blasting and dried promptly. They will go mouldy if kept damp too long or bagged before internal moisture content is low enough. For home use, air drying on racks is adequate. Assisted drying is required commercially.
Orchard layoutGrafted trees are recommended for smaller orchards or where uniform nut quality is critical. Certain seedling lines come remarkably true to the parent.

In humid climates, timber may be the preferred objective. Where timber production is required, initial spacings should be 4 x 5 metres. Half of these should be thinned out in stages.

Where nuts only are required, use grafted trees at a maximum of 10 x 10 metres. Having more than one variety will assist with pollination.

Orchard ManagementFertiliser is required. Mowing or spraying under the trees enables easy nut collection. Roots stocks can be J. regia or the hybrid “paradox” for well drained soils. J. nigra is preferred for wetter soils.
Pests and diseasesApart from blight and root rots in poorly drained soils, other diseases are only of nuisance value. Blight can be controlled with copper sprays. No other compounds are yet registered for use.

Puriri moth can cause damage to young trees by ringbarking. Walnuts are palatable to horses and sometimes to possums.

Shelter and IrrigationShelter is important, even in mild situations. Wind slows the growth down and cools the microclimate. Irrigation could be useful for very dry areas, especially during establishment. Don’t over water.
Payback PeriodGrafted trees can start bearing after a year but an economic crop will not be achieved until at least 8 years under ideal conditions. Cropping is directly related to tree growth (and variety). The slower the growth, the longer the wait for nuts. As seedlings are generally more vigorous, they may be quicker to bear nuts

Chestnut Chart

Species or hybrids between Castanea sativa, C. mollisima and C. crenata (Spanish, Chinese and Japanese)

Recommended Varieties1002, 1005, 1015, Disk II, Mayrick King, Mayrick Queen
ClimateNot fussy, as long as they are clear of salt spray
SoilCritical. Must be free draining down to 2 metres. Soil fertility not usually a problem.
MarketsNuts mostly exported and local market is fully supplied, but expanding. Overseas markets pay highest prices for processing quality nuts, but this has not yet happened here. A recent development is the production of chestnut meal in NZ for the food industry. Chestnut timber is also highly sought after overseas. Timber from C sativa is naturally ground durable.
HarvestingThe nuts fall to the ground and must be harvested within a day to avoid deterioration. Prickly burrs present a problem. Various machines (vacuum and hedgehogs) available to pick up nuts
Post-HarvestChestnuts are starchy and taste rather like kumara. They can be dried for use like flour. Usually stored moist in cool stores. Processing into meal involves cooking and pressing
Orchard layoutMinimum spacing is 6×6 m. Some growers are allowing much more room. Chestnuts must not be thinned by cutting trees down. Dying roots would cause fungal infections in the remaining trees. (Therefore dig trees out). Most growers are planting 3 varieties. Harvest has to be by variety. Nut quality is modified by the pollinator.
Orchard ManagementVery little is required except for mowing or spraying under the trees to enable easy nut collection.
Pests and diseasesPuriri moth, grass grub beetles, cicadas and opossums can cause serious damage on young trees. Very palatable to livestock. The fungus phomopsis affects storage of the nuts. At present no sprays are registered for use on chestnuts.
Shelter and IrrigationShelter is helpful in exposed situations. Irrigation can make establishment easier and increase crops. Both are important in severe climates.
Payback periodGrafted trees will start to bear after a year and should be giving an economic return by age 4. The pure Japanese varieties take a year or two longer.

Wednesday, 27 August 2003 – Updated: 2015-02-20