By Jenny Lawrence
While walnut trees have been part of the New Zealand landscape for over a century, an effort to source known walnut selections from overseas, carry out research and eventually begin planting walnut orchards did not start until more recently.
Zealand Tree Crops Association
The foundation for progress toward a commercial walnut industry in New Zealand started in the late 1970’s early and mid 1980’s. The impetus for this development was the establishment of the New Zealand Tree Crops Association [ NZTCA ] which grew from the earlier Canterbury Tree Crops group. Through NZTCA branches, a network of tree enthusiasts became apparent, particularly those with an interest in growing walnuts as a commercial crop.
The first European walnut cultivars introduced to New Zealand for new commercial orchards came through David Jackson who was a senior lecturer in horticulture at Lincoln University. David’s main interest was grapes but while visiting the Geisenheim Research Institute in Germany he noticed a walnut research block. David contacted the Canterbury Branch of NZTCA and asked if they were interested in importing walnut scion wood. Roland Clark, Doug Davies, Guy Goldsbrough, Rex Baker and David Murdoch were part of the South Island Walnut Action Group [ SIWAG ] which was a sub group of NZTCA and Canterbury Branch at the time, and after discussion around logistics and quarantine, five cultivars were sent and became known as Esterhazy, G120, G139 and G1339. The fifth did not survive and G1339 went on to become NZ Purple but in Germany it had been named Red Danube.
Guy Goldsbrough propagated the German cultivars and eventually they were planted in a research block at D.S.I.R Lincoln and in front of the Horticultural Research Area main building at Lincoln University.
A North Island Walnut Action Group [ NIWAG ] was formed during the same time as the South Island research was happening. This group included Nick Nelson Parker, Chris Ryan, Diana Loader and Vernon Harrison of ‘Harrisons Tree Nursery ‘. Vernon, along with others, had imported Wilsons Wonder, Tehama and Franquette. This group also set up trials with overseas cultivars and New Zealand seed material that showed promise. Chris Ryan found Meyric in Hawkes Bay and David Murdoch judged it the winner of the NZTCA walnut competition at the Nelson conference in the early 1980’s. Vernon Harrison propagated Meyric and another walnut cultivar of interest, Shannon.
In Ashburton, American cultivars Serr, Vina, Chico and Hartley were imported by a grower. ‘Millichamps Nursery’ in Ashburton propagated the selections for sale. After all of the energy put into the early importing of overseas walnut cultivars and establishing research trials, expertise in the difficult area of walnut propagation developed and Guy Goldsbrough, Vernon Harrison and David Murdoch led the way. By now more grafted material was available to growers.
In the early 1980’s the first tree enthusiast to set up a commercial orchard was Bernard Vavasour who was a beef farmer in the Awatere Valley, Marlborough. Bernard planted both American and European cultivars and propagated enough to establish a sizeable orchard of over 500 trees. Bernard’s favourite varieties were Serr and Hartley. Unfortunately, when Bernard sold his farm, the new owners cut down the walnut trees and planted grapes.
In 1984, Otto and Valda Muller from Central Otago, near Bannockburn, introduced American and European walnut cultivars to a research block to try and establish which cultivars performed well in the difficult Central Otago climate. Unfortunately, the research orchard was destroyed by fire when about six years old and both the trees and potential value of the research were lost. Fortunately, the charred trees sent out shoots the next spring and they managed to graft these and establish their main orchard which is now well over 1,000 trees. Valda cautions about which cultivars are good for Central Otago as each season has its challenges but although Franquette is very slow to mature and yield nuts, they are worth waiting for! Franquette is also a very late leafing cultivar which hopefully avoids late frosts in prone regions.
Further cultivar research continued in Canterbury with the assistance of Lincoln University plant scientists, firstly with Dr Bill Nagle, followed by Dr David Mc Neil. When irrigation issues appeared at the D.S.I.R. site and the impending dis-establishment of D.S.I.R. nationally was apparent, a decision to relocate the walnut trial area was made. Lincoln University, through Professor Richard Rowe, offered a new trial site at the Horticultural Research Area. A contract to operate was signed up between the university and the Canterbury Branch of NZTCA. All of the known imported cultivars were re-established at the new site along with two known NZ cultivars, Meyric 1199/4 from the NIWAG and Stan Ble 300 from Marlborough.
Continued progress to find more walnut cultivars was sped up with the initiation of the Great New Zealand Walnut Hunt through NZTCA. Over 350 samples of in shell seedling walnuts were sent to the Canterbury Branch. Guy Goldsbrough obtained a copy of the Californian Assessment Sheet including data sheets from the Californian Walnut Breeding Programme and with a few minor alterations this was used as the basis for judging the entries. Lincoln University kindly provided laboratory space to carry out this work after walnut enthusiast, Rex Baker, found the inundation of walnut samples outgrew his living room. Rex was a tireless supporter of the cause and being a retired super annuitant spent a huge amount of time pulling the details and results together. After judging the top ten cultivars, the culmination of the walnut hunt saw the establishment of another trial area beside the already established one. David Murdoch propagated the plant material from the original parent trees and the trial was planted in 1987.
Several walnut orchards with plant material from the trials were established before final recommended varieties were announced from the research. In Canterbury, two orchards in Halswell [one being Rex Baker’s trial area], in Otago, one in Wanaka, in the North Island one in Wanganui. Only two of these orchards remain as both the Halswell orchards were purchased for property developments and the trees were chopped down.
A Surge of Interest
During the late 1980’s, and following on from the early plantings, a surge of interest, particularly in Canterbury, saw the continuation of the sharing of information about walnut growing in NZ both through NZTCA , Lincoln University and the newly formed Southern Nut Growers Association (SNGA) SNGA was instrumental in bringing the commercial element to the developing walnut and hazelnut industries and focussed on financial aspects including maximum spacings of trees in the orchard, tree management for early return and equipment required for orchard development. As time went on each of the two nut industries decided that they would prefer to encourage and support their own grower base and so in 2001 the NZ Walnut Industry Group (NZWIG) was formed.
Two cultivar trails continue today one started in 2005 and the other in 2011. For the 2011 trial NZWIG imported three varieties Lara, Tulare and Howard
Throughout the early years of walnut industry development there was always the question, “Who will process, promote and market the walnuts coming on stream?” In shell walnuts could always be sold at the farm gate after washing and drying and any grower could do this. But what about processing in shell, – cracking, sorting, packaging, branding, marketing and selling. This was a big task that required meeting Food and Health Standards and OSH as well as purchasing equipment to do the job.
Over the last three decades three companies have taken on this challenge.
New Zealand Nut One, operated by Otto and Valda Muller near Bannockburn in Central Otago.
A Cracker of a Nut, West Melton, Canterbury. Established in 1996 by Malcolm and Jenny Lawrence. Now owned and operated by the Walnuts New Zealand Co-operative Ltd.
Uncle Joes, Marlborough. Owned and operated by Malcolm and Jenny Horwell.
Dr Geoffrey Savage of the food group at Lincoln University has been a key person assisting with the science surrounding value added products such as walnut oil, paste and flour. He has also assisted with the importation of walnut cultivars and testing quality standards and continues to work alongside NZWIG..
NZWIG is well situated to continue assisting walnut growers in all aspects of the and to promote walnuts as a healthy food to eat.
Jenny Lawrence 2017