Northland avocado nursery leads the way

Maunu's Stephen Wade in his 3-year-old intensively-planted avocado block which is already producing 20 tonnes of fruit per hectare Photo / John Stone

A multi-million-dollar Northland nursery is this season selling $6.8 million of new young avocado plants as the fruit's $144m New Zealand industry booms.

Maunu's Lynwood Nursery has this season produced 156,000 young avocado plants which are now heading off from the nursery for commercial growers around New Zealand to plant over the next six months.

The nursery is one of the top two of only six in the world producing clonal avocados and also New Zealand's biggest producer of young avocado plants produced this way - using genetic material sourced from Maungatapere, California and South Africa.

It has 100,000 cloned and 56,000 seedling plants in 40,000 square metres of polyhouses on its property near Whangārei – all already sold out in a six-month planting season that began this month.

"We can't keep up with demand," Stuart Pascoe, Lynwood Nursery chief executive officer said.

Lynwood Nursery director Stephen Wade started developing cloned avocado nursery production in 2000, taking more than a decade to adequately refine the "very difficult" process to the point of commercial sale.

The nursery's clonal avocados are sold around the country.

New Zealand's biggest new plantings are using the nursery's cloned avocados in places including the Far North and Tapora, west of Wellsford. Seventy per cent of the nursery's last five years' production has been used in massive Aoupouri Peninsula avocado plantings north of Kaitaia - about 730,000 trays, almost a quarter of New Zealand's avocado crop now comes from the Far North.

Ady Sime at work producing some of the 100,000 clonal-grown avocado plants grown in 40,000 square metres of polyhouses at Maunu. Photo / John Stone

The nursery's first export of the young clonal avocado plants will take place in November with shipment to Japan. It has just this month been cleared to export to China as well - a New Zealand first.

Lynwood Nursery's cloned avocado seedling production has increased dramatically since beginning full-scale producing in 2013 - that year producing 10,000 plants, 2014 - 12,000 plants, 2015 - 15,000 plants, 2016 - 30,000, 2017 - 60,000 and in 2018 - 90,000.

The New Zealand avocado industry goal is to by 2040 grow 10,000ha of the fruit crop across New Zealand (and a billion dollar industry) – almost three times the country's current 3800ha in avocados.

The Maunu nursery now has 44 staff working on clonal avocado plant production (and six on seedling-grown young plants) compared with a total of eight staff working on producing these two types of young plants in 2015.
November will see 200 clonal avocado plants heading to the business' Japanese joint venture.

These plants will be used to trial that country's first outdoor avocado growing orchard. Japanese avocados are grown indoors to avoid damage from the as many as 17 typhoons that hit the country each season.

New Zealanders using or investigating using the Maunu cloned plants include Māori from as far north as Ngataki, 60km from Cape Reinga at the top of New Zealand.

A Coromandel grower is using the cloned avocados too - looking to establish New Zealand's most southern and first local large-scale avocado orchard in Oamaru, North Otago.

Lynwood Nursery's Stuart Pascoe, chief executive and Grace Shen, international business manager amid the business' clonal avocados. Photo / John Stone

This will bring commercial-scale avocado production to almost the full length of New Zealand, the crop grown over a 1700km distance and significantly, 10 degrees of latitude – and temperature change - from north to south.

Others include Waiheke Islanders and a Rangitikei (lower North Island) producer who will be planting 1200 of the Maunu-grown cloned avocado trees at the start of November.

The young clonal plants are predominantly being used for an increasingly-popular new production system where avocados are planted out in ever-greater densities.

Up to 1600 young plants per ha are planted out – eight times the density of New Zealand's traditional 200 trees per ha planting density.

Northland is at the forefront of the new intensive planting approach. New Zealand's most densely planted avocado block - with 1600 plants per ha - is in a Waiharara orchard just north of Kaitaia.

New Zealand's intensive avocado plantings are at present typically up to about 600 trees per ha.

The trend towards greater density is set to only increase.

"It's definitely the way the industry is going," Sarah Williamson, Lynwood Nursery customer and technical support said.

The intensive avocado production systems use a new approach, twice-yearly pruning to keep intensively grown trees to only about 3m high – and sometimes shorter. The new Rangitikei producer will be pruning the trees to only 2m tall.

Shorter trees are revolutionising the industry which has had to until now use expensive mechanical cherry pickers to reach the top of 12m high mature avocado trees to harvest the fruit. Harvesting the shorter trees that are a key component of intensive planting be done manually.

Williamson said shorter trees' harvesting costs were around $65/bin for intensive orchards compared with the $120/bin for traditionally-planted less intensive crops.
Shorter trees mean manual pruning saws and loppers are all that's needed to prune the trees.

Other benefits include better quality fruit with a much greater percentage of export avocados in crop harvests – up to 80 per cent of fruit being in this category compared with 40 per cent in traditional more extensive production orchards.

The shorter trees also mean less problem with wind damage and trees being more protected behind their shelter belts.

Intensive orchard production benefits also include close-grown trees reaching their full production potential per hectare within four years – compared with seven years for the more extensive traditional growing systems.

Closer-grown trees create more warmth amongst orchard plantings. This boosts growth and performance. Lynwood Nursery trials show 3-year-old intensively-grown trees producing 20 tonnes of fruit per ha.

"This production is supported by doing the horticultural production basics well," Pascoe said.

The Maunu nursery took some time to perfect the process. Wade said he started getting into clonal avocados as a result of looking at the international literature on horticultural crop production.

"They were obviously going to the better than seedlings," he said.

One reason for this was the performance consistency.

It took Wade about 15 years to refine the avocado cloning process to the point of being able to produce reasonable commercial quantities of new young plants.

"Avocados are the most difficult plants in the world to propagate," Pascoe said.
It takes about two years to produce a clonal avocado seedling.

The Maunu nursery's plants are produced for resistance to avocado root rot disease phytophthora – a major scourge for New Zealand growers.