Oregon-based insulated stainless bottle brand Hydro Flask is launching a collaboration with beloved picture book author Eric Carle. Sales begin on March 20, 2026 (Friday/public holiday) — "The Very Hungry Caterpillar Day" — at HUNGRY MARKET, the shop adjacent to PLAY! PARK ERIC CARLE in Futako-Tamagawa, Tokyo. The HUNGRY MARKET online shop will also start carrying the items on the same day.
March 20, the vernal equinox, has been designated "The Very Hungry Caterpillar Day" by connecting the arrival of spring with the story of growth depicted in the picture book. The collaboration stems from a shared respect for nature: Eric Carle's work consistently celebrated the beauty of the natural world, and Hydro Flask has long championed a move away from single-use plastics.
Hydro Flask × Eric Carle
(From left) 12 oz Kids Wide Mouth -Caterpillar/Fruit, 12 oz Kids Tumbler With Straw Lid -Caterpillar, 12oz Tumbler & Bottle Set -Caterpillar
The bottles retain Hydro Flask's high insulation performance while covering the exterior in Eric Carle's vivid and distinctive artwork. The durable powder-coated bodies feature iconic characters from The Very Hungry Caterpillar, depicted as if they have leapt straight from the pages of the picture book.
The bottles come with a boot that protects against drops and scratches, and include a space to write a name — making them a great choice as a child's first personal bottle, from daily commutes to school to weekend outdoor adventures. The design encourages families to embrace sustainable choices by reducing single-use plastic in an enjoyable way.
Coming Soon...
A second collaboration is also in the works. What design will appear on the next bottle? Details are still under wraps, so stay tuned for the announcement.
About the Collaboration
The HUNGRY MARKET store manager commented: "I selected these bottles because Hydro Flask's toughness and beauty make the perfect partner for children's everyday adventures. The vivid colors reminiscent of Eric Carle's picture books are energizing just to hold, and make daily outings more fun. I hope you and your child can find your favorite together."
PLAY! PARK ERIC CARLE
PLAY! PARK ERIC CARLE is the world's only kids park themed around the picture book world of Eric Carle. Visitors can freely explore nine areas including a green maze and athletic atelier. The park embodies Eric Carle's belief in the importance of learning through play, offering experiences designed to bridge children's growth.
Address: Futako-Tamagawa Rise Shopping Center Town Front 8F, 2-21-1 Tamagawa, Setagaya-ku, Tokyo
Website: https://playec.jp/
HUNGRY MARKET
HUNGRY MARKET is a picture book goods specialty store adjacent to PLAY! PARK ERIC CARLE, curating merchandise from the Eric Carle collection. The shop carries a wide range of goods inspired by various Eric Carle works, including the worldwide bestseller The Very Hungry Caterpillar, as well as From Head to Toe, Papa, Please Get the Moon for Me, and Dream Snow.
Address: Futako-Tamagawa Rise Shopping Center Town Front 8F, 2-21-1 Setagaya-ku, Tokyo
Online Shop: https://hungry-market.playec.jp/
