How had Gus planned a Dutchthemed picnic?

That weekend, Hazel and her parents go to the farmers' market and while there Hazel gets a call from Gus saying that he will be waiting at her house when she gets back. He brings her bright orange flowers and asks her parents to take her on a secret date. He takes her to the sculpture garden behind the art museum where a large skeleton sculpture called Funky Bones is on display. He reveals that this sculpture is by a Dutch artist, that the jersey he is wearing as a Dutch basketball player, and that orange - the color of her flowers along with all of the food he has brought for a picnic - is the national color of the Netherlands.