It was the deepest point of winter, and Sarah thought she’d cheer herself up by looking at a seed catalogue and choosing the flowers she would grow that summer. As she leafed through it, she was assailed by a sense of doubt. Surely it was too early, surely it was too great a risk, surely she was pushing her luck? The flowers might never bloom after a winter like this. She had best bide her time.

She went out into the garden, through the gate and into the copse beyond. It had been raining heavily, and large drops hung from the bare twigs. They would fall off soon and feed the ground. Sarah looked closely at them. One of the raindrops seemed different: larger, shinier, and with something inside it that seemed to wriggle. She stretched her index finger out: the raindrop was sticky and somehow clung to her skin. Horrified, she looked at her hand, but could not shake the droplet off.

Very well. Sarah went into her greenhouse - empty at this time of year - and managed to peel the object off and put it into a small plant pot full of soil. She covered it with fertiliser and left it, just to see what would happen. Not much for a day or two, and then a small shoot emerged. So far so good. But she had never seen anything grow at this speed. A leaf sprouted, two, three, and the plant was so strong that it burst the pot open. She had to repot it every day, and after a week it needed her biggest pot, the one that she had intended for a small tree. One side of the greenhouse had soil rather than paving, so she dug it over and put the new plant in.

After a month the plant was pressing hard against the glass and filling the entire greenhouse, and Sarah could hardly squeeze in to water it. It seemed to rustle a lot and to squeak sometimes. It began to moan when the wind blew: a low sound, though it was difficult to tell whether it was a sound of desperation or desire. Then the spring started in earnest, and the temperature rose. The greenhouse was in a sunny, sheltered spot, and one day Sarah heard an enormous explosion: she rushed outside and found that the plant had burst through the greenhouse, shattering it into thousands of pieces. She went out with her dustpan and brush to remove the shards.

There it sat now, free in the air, almost buzzing in the sun. Sarah had thought that the plant would grow up, but instead it grew out, and spread to fill the patio. Then it produced a huge bud - initially about the size of a grapefruit, but then the size of a melon, a football, a yoga ball. A seam opened up down the side, then two, then three, and finally the bud split open to reveal an enormous red flower.

But this was no ordinary flower. It was 6 and then 8 feet across. The scent was like none Sarah had ever known, sweet beyond imagining, a little sharp here and there, but none the worse for that. The stamens trembled. Unsure as ever what to do next, Sarah hesitated on the threshold and then stepped in and sat down.

She knew that the petals might close over her at dusk. It wouldn’t matter much. They might open again, they might not. But for the moment she was happy to be where she was, in the colour and perfume and sound. Summer had come at last, though not in its habitual form. And after all, tomorrow might never arrive. Though it usually did.