Because breastfeeding is not as normalised as it could be, not many women talked about the difficulties, she said.
"I guess I wanted to go because I'm quite proud I am still breastfeeding because I had some trouble in the beginning," Ms Stenberg said.
Her boys Luke and Taylor Bracey, now 11 months, were among babies aged from 2 weeks to 20 months old at the event.
Organisers Charlene Morunga and Kylee Parker said they were amazed at the turnout, almost four times the number last year.
"Seeing all the mums come together and breastfeed together in one place was really cool," Ms Parker said.
"It's just to make people aware that breastfeeding is okay in public and it is the best thing for them, if you can do it."
The Big Latch On was part of World Breastfeeding Week, which runs from August 1-7. The event was started in New Zealand 10 years ago and has taken off globally, with around 30 countries now holding latch-on events.
Northland DHB lactation consultants Helen Parker and Janine Parsons were thrilled by the level of support.
The day was about celebrating breastfeeding mums, Ms Parsons said.
"Some have had a really hard journey to get there and we know they have shown a lot of commitment and perseverance in wanting the very best for their babies," she said.
Twenty-two local businesses donated spot prizes.