Experts say it's beneficial to New Zealand for the children of Asian parents to know their language and culture.
Sarany Sheridan is teaching her daughters Kate, eight months, and Frances, 5, to speak her community language Khmer. Photo: RNZ / John Gerritsen
A report from the Asia New Zealand Foundation said the number of under-fives with at least one Asian parent doubled between 2001 and 2013, now accounting for 18 percent of preschoolers.
The study, 'Starting Strong: nurturing the potential of our Asian under-fives', said 89 percent of those children were born in New Zealand and most spoke English at home - but many also spoke an Asian language with one or both of their parents.
One of the report's authors, University of Auckland associate professor Elsie Ho, said that when the children grew older they wanted to use English more and the heritage language less.
She said the government could help by providing more resources to support recognition of Asian cultures in early childhood and by training more bilingual early childhood teachers.
Asia New Zealand Foundation chief executive Simon Draper said the children's knowledge of Asian languages and culture should be valued more highly in their own homes - by schools, and by New Zealand society in general.
He said New Zealand needed people who understood Asian cultures and languages because seven out of 10 of New Zealand's trading partners were Asian nations and involvement with Asia was likely to grow further.
"The value they bring is understanding of a part of the world that is becoming more and more important to New Zealand."
Mr Draper said Asian parents should be encouraged to share their culture and language beyond their homes.
But he said there was also a role for the government, particularly in developing a national plan for language learning.
The chief executive of Business New Zealand, Kirk Hope, said the high proportion of Asian under-fives represented a great opportunity for New Zealand.
"The opportunity not just with China but a number of other Asian economies over the next 20 years is going to be significant from a business perspective.
"We're going to need people with the skills to be able to engage properly so we can maximise the opportunities there."
Mr Hope said there was a lot the government could do, including encouraging more speakers of Asian languages to train as teachers and providing more resources for teaching Asian languages in schools.
"There's probably an opportunity to run education campaigns to encourage Asian parents to keep using the language with their kids. It really is a great resource for New Zealand."
The foundation's education director, Jeff Johnstone, said the new government was considering more support for Pasifika languages and it should do the same for Asian languages.