Rush Munro's granddaughter Judith McMillan said it was wonderful to see everyone out enjoying the gardens.
"How amazing to see so many people still loving the icecream and the parlour that my grandfather started with 10 pound in his pocket, 90 years ago.
"What a wonderful day it was with families turning out to eat, laugh and be merry, I am so happy I got to be part of the special celebration."
There was cake to share, The Hits hosts Martin and Sarah gave out spot prizes, and there was a surprise visit from Santa Claus.
Staff dressed up in old fashioned outfits and Rush Munro's general manager Tom
O'Sullivan said they scooped more than 2500 icecreams during the day.
"It was a really good vibe among the team yesterday, they all did a fantastic job and were still buzzing at the end of it.
"The celebrations went really well and it was good to see so many Hawke's Bay locals join the fun and take a trip down memory lane. It was also fantastic to see the families of the previous owners travel from far and wide for the significant milestone."
Although Saturday was about celebrating the past, the multi-award winning business are looking to the future with plans to begin exporting their product.
Mr O'Sullivan said the icecream manufacturer would soon be launching into the international market - with Australia "the logical next step", and Asia first in line.
The company has also just secured a licence to export to China and hoped to begin exporting there, and to other westernised Asian countries soon.
To cope with new demand, next year the business will welcome new machinery to speed up some manufacturing processes, although Mr O'Sullivan guaranteed they would retain their boutique feel.