The first stage was to study the score and work out which bits were singable. Last April, when I was just beginning to write A Season to Sing, I spent a few days in Venice to get into the zone. While I was there I attended a performance of The Four Seasons in Vivaldi’s church, sitting in the audience with the score on my lap, circling any bits which I knew would be good to sing. I’ve always approached choral composing very much from a singer’s perspective because it matters to me that everything I write feels nice to sing. With many of the movements the solo violin part became the right hand of the organ accompaniment while the choir parts were derived from the accompanying string lines of the Vivaldi. The slower movements (usually middle movements within each season) leant themselves more easily to being sung. Vivaldi’s melody-writing is absolutely sublime – sometimes I had to pinch myself to realise that they’d been written 300 years ago.

I decided early on that I wanted to keep all of the keys the same as in Vivaldi’s original. Sometimes, when you’re arranging instrumental music for voices, it makes sense to transpose into a different key, as was often the case when I was singing Bach in the Swingle Singers. I’m pleased that I chose to keep Vivaldi’s key structure because it helps my piece to retain more of the spirit of the original. Keys have certain colours and Vivaldi’s choice of keys fits perfectly with each season: the bright and joyful E major for Spring, the languid G minor for a hot and stormy summer and so on.

Tell us more about the texts you have chosen for A Season To Sing….

Sourcing the poems, hymn texts and Bible passages for each movement was an integral part of the process. It mattered to me that the words might sound as if they could have inspired the music, even though it was the other way round, of course! This meant matching their rhythms, rhyme schemes, phrase lengths and cadences to Vivaldi’s melodies whilst simultaneously enhancing his musical descriptions of different aspects of the seasons.

Vivaldi’s manuscript helpfully contains the Italian sonnets he wrote as the basis for his music. For the opening movement of Winter, I chose to adapt one of these sonnets, L’inverno, to create a soundscape. This is followed by the only wordless movement of the piece which I arranged in homage to Ward Swingle, the founder of The Swingle Singers, who became a close friend during my tenure as the group’s Musical Director. The remaining texts are from the Old Testament (Genesis, Exodus, Psalms, Song of Solomon and Zechariah), poems by two 19th-century English poets Emily Brontë and Eliza Cook, a hymn by Henry Alford and a Thomas Morley madrigal. It’s an eclectic mix into which I added the words of Ecclesiastes 3:1-8 (beginning ‘To every thing there is a season’) and set them in two movements which serve as bookends to the twelve Vivaldi movements.

In the final movement I’ve worked in a phrase from the Requiem Mass, Dona nobis pacem, (grant us peace) which helps to emphasise the ‘time of peace’ from the Ecclesiastes passage. Our world needs peace now more than ever.

What do you hope choirs/singers will enjoy in singing and performing this music?

My intention is for choirs to have a lot of fun with this piece, especially with the passages which are not so much “sung” as “performed”. For example, in SPRING there’s the birdsong chorus of whistlers and the nasal, bagpipe drone; in SUMMER there’s the call of the cuckoo and a storm created with body percussion; in AUTUMN, what were originally hunting horns are now a trumpet fanfare in praise of harvest; in WINTER the opening movement is half-sung/half-whispered to give the effect of the cold and the singers are required to shiver from time to time to maximise the effect!

As I always do when I’ve finished a new piece, I (together with my brilliant husband) have recorded every vocal line so that I can make sure that they all feel good to sing. Anything that feels awkward gets changed. So choirs can expect to have a lovely time learning and performing this piece. Nothing sits too high or too low and it’s deliberately on the easier side because I want all choirs to be able to sing it, from church choirs and chamber choirs to choral societies and community choruses and everything in between.

And what do you hope audiences will take away from the performances of A Season To Sing?

I imagine most people, even those who would profess to know nothing about classical music, have heard at least some parts of The Four Seasons before so I’m hoping that, as the performance unfolds, the audience will be thinking “ooh, I recognise that tune” from time to time. I’m also confident that by hearing a performance of A Season to Sing people might come to appreciate the genius of Vivaldi’s original concertos in a new way. Not only did he write great music but it is describing different aspects of the seasons – so clever!

Mostly I want audiences to feel joy when they hear this music. Performances should be visually as well as aurally entertaining and, because of the seasonal theme, they can happen at any time of the year. I love the idea that some concerts will be in the height of summer and others in the depths of winter! I hope that everyone will be able to locate a performance happening near them and that all of the choirs who put on a concert will have a lovely, big audience of smiling faces.