His Kent village garden shows signs of spring too, but there are no topiary gorillas trampling on the crocuses and the washing line is ominously empty, for the moment.
The man who hangs fish, bananas and three-cup bras out to dry in his much-praised picture books is busy with projects for two new publishers and planning trips to Australia and Venezuela. He is also a UK nominee (alongside novelist Nina Bawden) for the international Hans Christian Andersen award to be announced next month at the Bologna children's book fair.
However, the first note of despair in his 20-year career crept in recently during the early stages of work on four seasons of paintings for Voices in the Park. "I got through the winter section and couldn't imagine it in a bookshop. I was thinking of new ideas and worrying that they weren't commercial enough. That's the first time I've felt that kind of pressure, and I didn't enjoy it. I've always just thought of books I wanted to do.
"I was thinking of having a break from children's books and just painting, something I've never done. I wanted to be a painter but coming from my background [his father was a commercial traveller] I needed something that would lead to a job, so I did graphics rather than fine art.I thought it would be good to have a change."
Instead, he devised a book that could accommodate "a series of paintings I want to do" and also please fans of Willy, his popular wimpy chimp. With the outline for Willy the Dreamer complete, he has gone back to Voices in the Park with relish. "I've just started the first painting of the Spring section, and I'm excited again. And of course it's spring, which helps."
The Voices book, to be published by Transworld later this year, is partly a second take on The Walk in the Park, his second book. "I've always liked the text but I draw better now and I know more about making picture books work. I didn't want to just re-illustrate, so I've told a simple story from four very different points of view. Each story will also look different, painted in a different style."
The Winter paintings are not quite complete. Many of the expected Browne homages to Magritte will be added later. "I spend about three days finishing most of a painting, and leave something to go back to. It means I don't get bored." He has left empty picture frames, probably destined for a Weeping Cavalier and an unsmiling Mona Lisa. Subversive works of art are trademarks of his interiors along with early Habitat wallpaper and shades of Mike Leigh, a film-maker he admires, in the family dynamics.
He has captured the unsettledness of being young in his cast of loners open to adventure. His painted children (some modelled on his own son and daughter, or his younger self) are often scared and vulnerable, and their happy endings are equivocal. The family party on a gruesome outing in Zoo (Browne's own favourite book) and the glimpse of Hansel and Gretel's loveless home, frozen in the drab Fifties, are truly terrifying.
He has had his own scary moments, such as the mixed reception for his playful Alice in Wonderland - "it's been done so often and it's a book people feel strongly about" - and his collaboration with Ian McEwan on The Daydreamer. "That was something I couldn't turn down - it's a wonderful story - but I had to do it at night while I was working on something else and there was a lot of pressure. One of the difficulties was that Ian wanted the cover to be something very bizarre but I didn't want to use his best bizarre happenings - I was worried about taking away the writing and stopping the child imagining it. If you are illustrating your own text you can use the gap between the text and the picture." In Gorilla, for example,the strangest features of young Hannah's adventures are offshoots of the story. Going to the cinema with a gorilla is presented as normal- so it follows that Superman must be a gorilla too.
Willy the Dreamer, due out next year from Walker, is Browne's treat - his own daydream book, but with almost no words. Willy, the chimp of indeterminate age, will stave off mid-life crisis with a series of lavish fantasies in which he becomes a film star, a sumo wrestler, an explorer and more. "It's everything I wanted to paint, all at once," says Browne.
Time to bulk-buy the bananas and the clothes pegs.