"They're a very New Zealand fruit. People who love feijoas are very passionate about liking them and people who don't like feijoas are very passionate about not liking them.
"It's not all about the fruit, we like getting people into this education room in the Resource Recovery Centre, because there's a lot for people to take in while they're here."
The event encourages people to try new things and see what they can come up with in terms of recipes that incorporate feijoas.
"We also put three years worth of recipes into a book here which people can buy," Williamson said.
"I'm biased, but I like mine best, I'm a fan of lemon curd and passionfruit curd, I found a recipe on the internet for feijoa curd and I think it's just out of this world."
She said it was best served with a pancake or on a piece of shortbread.
Sustainable Whanganui trustee Lyn Pearson came up with the idea for the Feijoabulous Festival but she does not even like the fruit.
"I may need to escape because the smell might become too much for me," Pearson said.
"Feijoas have been described as a citizen's fruit because anyone can grow them, although we're a bit worried about what the guava moth is going to do to them."
Guava moths are currently found in Northland and have worked their way down to Auckland more recently. They drill into the flesh of fruit and destroy it from inside.
Pearson said feijoa smoothies were probably the most popular food on the menu and the biggest feijoa competition was one of her favourite parts of the day.
"One year somebody tried to cheat in our biggest feijoa competition, it was a zucchini and it was big.
"It didn't cut very well so I knew it was suspicious."
She was looking forward to a choir performance later in the day, which was a new addition and would feature a song called Bring me some little feijoas Sylvia.