You can never completely know another human being, least of all as a parent. And that’s fine. We all, as TS Eliot said, must “Prepare a face to meet/The faces that you meet”. But honest writers with a powerful gift for expression offer more of themselves, more clearly, than most. So there was awe and wonder mixed with all the grief when, after his early death nearly seven years ago, I found a mass of poems, notes and logbooks by my son Nicholas. He was 23.

I always suspected that he wrote more than he ever showed, and we knew about his adventures: crossing the Atlantic and Pacific as deckhand on the Dutch square-rigged ship Europa, visiting remote atolls, teaching young Koreans to climb the mast. But it was a surprise to find such detailed, vivid logbooks of the journeys, and delicate little poems on Post-it notes, and exercise books dotted – between university notes – with reflections on religion and literature, and satirically clear-headed polemics against the sterility of A-levels. There was even a kind of terrible wonder in the hints, vivid and terrifying, of the rising illness that finally caused his suicide.

I cannot say we got to know him better this way – he was a well-loved, lovingly remebered son, grandson, brother, nephew and cousin for 23 years. But we all got to know him differently: an adult self, a developing soul. Ink and pencil fade, so I typed it all out, setting the computer to a different font from my normal working one so there would be no temptation even to change a comma. And there it would have stayed, a family archive. But I showed the writings to his old tutor at St Catherine’s College, Oxford, Professor Duncan Wu, and he said, “You are publishing?” He suggested that we had no choice. “It is a testament of a remarkable young man... he describes what he sees as straightforwardly as he can, depicting his own motives and conduct with scrupulous fidelity to the moment.”

Of course one hesitates over the privacy of the dead, but as Nicholas’s grandmother said with surprise when she read it through, “There’s a reader expected in there, he keeps saying. ‘If you read this...’ and ‘Sorry, I must go back a few hours.’” So we published, with brief, necessary, explanatory links from me because it was never designed as a whole book. Publishers, of course, had tended to want more from me: the usual misery-memoir of grief. But it was his book, not mine, and still is. So we brought it out ourselves, becoming a scramblingly amateur publishing house (every reprint delivery meant the lawnmower had to stand out in the rain. That would have amused Nicholas no end).

And there has been great validation in knowing that the book has touched others, young men in particular, whose intense feelings are not often so publicly expressed. The composer Joseph Phibbs asked to set the poems to music, with remarkable results now performed and recorded; and the film-maker Daniel Simpson created an astonishing short film, which (and this would have made Nicholas laugh even more) won a prize at a Las Vegas festival in 2010.

The idea of a radio dramatisation came more slowly. We knew from a couple of literary festivals that the writing sounded good aloud: straight-forward and vivid. And during the initial shocked phase of the long grief, I had been much supported by Jeremy Howe, commissioning editor for drama at Radio 4, who had lost his wife Lizzie to murder years earlier. His recent book, Mummydaddy, is a brilliant, harrowing but also funny account of bringing up his daughters without Lizzie, but before that he made a film about her, and so he was a useful guide – among other things – as to how long you should leave a terrible personal event like this before trying to engage with it as art. Especially broadcast, dramatic art, which somehow feels more immediate and personal than publishing a book.

Time passed, and the project wouldn’t lie down and go away. Nicholas was, after all, a lover of radio, which amused and comforted him all his life, from a six-year-old’s addiction to old recordings of Hancock and Journey into Space, right up to the magnificently awful Alan Partridge. Karen Rose, skilful and immersed in the book, undertook to produce it; together we cut and shaped the material to create a dialogue between the finder of the writings and the vanished author.

So this became the moment when it felt right to hear the creak and rattle of a sailing barque at sea, and to give audible voice, from the great ship-shaped building of Broadcasting House, to the boy who wrote:

I sing, inside myself, the one wild song
Song that whirls my words around
Until a world unfurls
My ship’s new sail
I catch the dew and set a course amongst the ocean’s curls.

Afternoon Drama: The Silence at the Song's End airs today, 2:15pm Radio 4