We’re now into the Persephone Days, with fewer than 10 hours of sunlight – a time when rocket loses some flavour, but kale and carrots grow sweeter
For those of us in the northern hemisphere winter has arrived. And perhaps more importantly for the plant world, we are also entering into our Persephone Days.
This phrase (named after the Greek goddess of spring, who was abducted by Hades and whose mother, Demeter, goddess of agriculture, withheld plant growth until she was returned) describes the period of time when there are fewer than 10 hours of sunlight in the day (mid-November to early January in the UK, depending on where you are in the country). It’s the point at which most plants cease to grow.
If you sowed winter seeds in August, your timely efforts will mean that your overwintering crops will be well established and able to stand in the ground as we go into the fallow months. It’s helpful to understand how this Persephone period affects plants: not only does it explain why we sow seeds in summer if we want crops to be mature enough to make it through winter, it also helps us manage expectations.
On the farm where I work, we had a greenhouse and polytunnel filled with hardy crops last winter – including rocket, mustard leaves and land cress – so we were able to pick leaves through most of the cold weather, although remained mindful that there wouldn’t be any new leaves emerging until mid-February.
If you’re lucky enough to have leafy crops ready to be harvested right now, pick them as needed so you minimise the chance of wasting precious leaves.
The intensity of sunlight also declines as we go deeper into winter, which affects how much a plant is able to photosynthesise. We found that some of the edible plants we were harvesting from during the cooler months – rocket sticks out in my memory – provided lighter, less substantial and less intensely flavoured leaves. Having said that, the drop in temperature also prompts certain crops, such as kale and carrots, to convert starches to sugar, and they taste sweeter as a result.
The number of daylight hours – or the duration of uninterrupted darkness, to be more accurate – also has an effect on flowering plants. Short-day plants such as chrysanthemums form blooms when the length of the day is under 12 hours, whereas long-day plants such as beetroot and lettuce will develop flowers when days are longer than 12 hours. Tomatoes and corn are examples of day-neutral plants that will form flowers no matter how long the days.
Now that the time for active growth has ceased for the year, I’d encourage you to take your cue from the plants and consider slowing down, too. We could all do with tuning into the rhythms of the changing seasons, heeding the natural world’s call to rest and reflect.