Trees are great. Don't get me started on how clever they are

EKA: When Elisabeth is a girl she develops a special friendship with her much older neighbour, Daniel Gluck. Her mother protectively becomes suspicious about their bond, but she persists in seeing him anyway. What is it that draws her so much to Mr Gluck?

AS: Hmm. Well. When she walks past his door, music is always playing. His house is full of art. Love and the imagination are connected. And he's different from anyone else she's met. And she already sees him for what he is, past appearance, and that's how he sees her. And a hundred other tiny details. But above all, she, like he, knows somewhere at her core as soon as they meet that they're about to be the lifelong friends that they'll become – I have a theory that we do know our lifelong friends, we intuit it as soon as we meet them. It's something about recognition. And love takes all sorts of forms that the cliched archetypes of love don't habitually leave much room for.

EKA: Like in many of your other books, trees play an important factor in this novel. There are descriptions of trees changing, people dressing up as trees and transforming into trees. What significance do trees have for you?

AS: Trees are great. Don't get me started about how clever they are, how oxygen-generous, how time-formed in inner cyclic circles, how they provide homes for myriad creatures, how back when this country was covered in forests the word for sky was an old english word that meant tops of trees ... The sweetness they create. The things they help us create. The pollenation they make possible, their utter (mellow) fruitfulness. Their gestural uprightness plus bendiness, their suppleness in all weathers. Their shelter. Their ingenuity with colours, and with looking after themselves seasonally. Their organic relation to books. Like I said, don't get me started. And of course, autumn – the fall – the lifecycle of leaf, the leaf-cycle of life. 'He who has kissed a leaf / need look no further' – William Carlos Williams. There's a Norwegian poet who everybody knows in Norway, he's like Burns is in Scotland, like Wordsworth in England, his name's Wergeland, and when he died, quite young, one of the last things he said before he went, was 'kiss next year's roses for me.' That's just the tip of what I feel about trees.

EKA: Your previous novel How to be both featured a young person's fascination with a somewhat forgotten artist. In this novel Elisabeth actively researches Pauline Boty, Britain's only female Pop Artist, who is now somewhat obscure. What drew you to writing about this artist and the character's preoccupation with her?

AS: I knew a book about autumn would be about the shortness of life – there's no avoiding Keats, after all, and too right there isn't. And when I happened on a Boty picture, so full of brightness and vivacity, and then learned her life circumstances, and looked at more and more of her extraordinary and vital work, and saw how she went about demolishing the borders and divisions and given limitations for a young woman of her time, I knew she'd figure one way or another. When I saw how she asks questions of the image, of the replication of the image, and our relationship with the image, it felt even more true to now; she saw it all – worked on and with the skills we need right now in a world blasted by image – fifty years ago, and when I sensed her skill too for incorporating what she called the 'nostalgia for NOW' into her work – and how her contemporary originality was so troubling that after her death she disappeared, just vanished, pretty much overnight, from the culture she'd not just embodied but helped to make possible – and then how she'd re-emerged, against the pretty tragic odds of her own short life – it was a cyclic story in itself. The cyclic structure, I'm beginning to realise, is a comic structure, I mean comic as opposed to tragic. It's about renewal. It'll always be about revitalisation.

So I think I knew to trust to such a serendipity. And I'm so unbelievably happy to have her kick-ass presence, her grace, her boundary-cancelling creativity and energy, that sheer joyous vitality, in a book so much about the divisions, locally, nationally and internationally, that we're facing both literally and rhetorically right now.