Wow, for a story based on a children's book, this is one downer of a story!
The short (20 minute) anime is definitely laid out like a young children's book, with a simple story and just three characters, simple backgrounds, and a kindly narrator that will speak a few sentences of story, followed by a minute or two of music, then more story.
It's about the love story between a young puppy dog and a giant anthropomorphic rose. Yes, you read that right. This is the trippy-dippy Seventies, after all, and why not a kiddie story about love between an animal and a plant? All is well...until the introduction of evil Mr. Crow (cue the overdramatic villain music so you know he's bad). At times their antics devolve into Looney Tunes style chase scenes. But as I said at the beginning, this is a downer of a story, so you know that tragedy is in the cards.
Why anyone would want to traumatize their young children with this story is beyond me. But so it goes.