Ms Pouwels said she thought the business would be a small, part-time hobby, but the "tea" has been very popular.
"I think Kiwis like the health benefits. There are a lot of antioxidants and stimulants in the tea that is very good for you," she said.
Mate contains a moderate amount of caffeine but is not bitter like coffee.
The business's warehousing facilities are on the North Shore in Auckland, and the company operates with a full pick-and-pack capability.
"We have partnered with Fastway Couriers and PBT transport for nationwide freight services."
Born in Argentina, Ms Pouwels moved to New Zealand in 2001 and it was Hector's dolphins that led her here.
"I am a biologist specifically interested in dolphins, and I knew about Scott Baker's work with dolphins in New Zealand. I met him at a conference and he invited me here to study my PhD."
It was later she met her husband, who helps run the business, and she had their children.
Ms Pouwels said she has been to Whanganui a few times and thinks that it is a beautiful place.
"There is a very wide community of Latin Americans that live in Whanganui and I know lots of Kiwis like our tea because of the health benefits."