The Wade family bought the Lynwood Nursery property in 1941, planted 4ha of avocados in 1983 and started nursery production of trees in 1988.
Sales started climbing after trialling for clonal rootstock production began in 2000, with more than 10,000 trees produced in 2001, 30,000 in 2009 and 70,000-plus last year.
Lynwood general manager Stuart Pascoe said about 150,000 seedling and clone trees had been produced this year.
Every week the business received requests from southern Africa, Asia, Europe and other parts of the world to supply trees as the health benefits have put avocados on menus around the globe.
"We are expanding flat out and are basically sold out for the next couple of years," Mr Pascoe said.
"If someone ordered young trees from us now, we couldn't supply them until 2019."
It's big business with seedling trees priced at around $20 each plus GST and clonal trees almost double that price.
Fruiting scions available from Lynwood include Hass, Reed, Bacon, Zutano, Ettinger, Fuerte, Edranol, Vista, Maluma Hass, Carmen Hass and Gem.
The last three are protected plant material available only to members of the NZ Avocado Growers Association and buyers must agree not to propagate them.
The Gem avocado is a newcomer in this country.
The Seeka produce company at Te Puke has acquired the New Zealand rights to the variety, and Lynwood at Whangarei and Riverson Nursery in Gisborne are the only two nurseries licensed to build up stocks to supply growers.
Seeka CEO Michael Franks said Gem had several advantages over the dominant Hass variety grown in New Zealand, including Gem being less prone to alternate bearing, which had made it difficult for the New Zealand industry to achieve consistent year-on-year production.
Gem was also a high-yielding variety that could be planted at a higher density than Hass and was easier for growers to manage, he said.
And it matured a little later in the season, meaning the fruit would help fill the post-Christmas/New Year gap in the market.
Seeka general manager growers and marketing Annmarie Lee said Gem would give growers a competitive advantage in the marketplace.
"The Australian market is usually very strong in January and February, and this will allow us to spread supply more effectively and maximise returns for our growers."
The Gem variety was discovered in the 1980s, with Seeka chief technical officer Dr Jonathan Dixon first becoming aware of it 16 years ago when he saw it growing in California.
Seeka acquired the New Zealand rights from the master licence-holder, Westfalia, in 2014.
The cultivar, the company has, came out of the University of California Riverside Avocado Breeding Programme.
"Our focus over the past couple of years has been to get mother trees established and build those numbers up so we have a good supply of budwood for grafting," Dr Dixon said.
The first major planting of about 6000-9000 trees is due in spring 2017, and the first commercial quantities are expected in 2019-20.
