We have now reached November, and finally there is a noticeable chill in the air. In the Botanical House, the tomatoes have finished fruiting and there is nothing left for us to do with the plants except pull them up and put them in the composter. In fact, all our summer plants have pretty much finished, and it would be easy to think it’s time to just tidy up and wait for next season when we can start again…
… except that everything doesn’t stop – it just changes focus. Cabbages, broccoli and sprouts are almost ready; carrots, parsnips and turnips are ripe and can be harvested for winter stews and soups. Under glass, we have repurposed guttering as growing channels for winter salad crops, basil shoots, kale shoots and rocket which we sow little and often so that we can cut fresh shoots all through the winter. Kale is a revelation – incredibly sweet and tender in a winter salad when cut young, and it will grow through the whole season. If you think you don’t like kale, you should really try ours!
We have also been experimenting with growing daikon radish. The oil from the seeds is used in our Botanical Shine™ Nourishing Hair Oil, and is chosen for its moisturising properties. However, if you’ve ever eaten it, you’ll find it’s a vegetable that will change the way you think about radishes – best eaten cooked rather than raw, it is an essential in many Asian dishes. In Korea they are used in some Kimchi recipes, and Chinese Dim Sum use shredded daikon to make the classic turnip cake. in Mauritius, it is used to make a vegetarian version of the popular Boulette Chouchou dumplings.
As it can grow up to 30cm in length, daikon is normally planted directly into the ground so that the root can reach its full length without interference. We sowed the seed in September under glass, and to avoid the frost over winter, we repurposed some more old drainpipes which, when filled with a mixture of compost and grit, provides a perfect medium for the transplanted seedlings to grow through.
Daikon has another, perhaps less well known value as a natural soil builder. Compacted soil is problematic due to its reduced ability to absorb water runoff and lack of aeration. Soil that is poorly aerated can cause root systems to die off, and rain water forced to runoff can cause flooding and leach nutrients out of the soil. Often there is nutrition deep in the soil that plants cannot reach, even when the top layers are depleted. The deep, wide taproot of daikon radish can work its way through the toughest, most compacted clay soil and open it up, going deep enough to make use of nutrients unavailable to other plants and bring them closer to the surface. This is sometimes known as biodrilling. The leaves act as a cover crop to further reduce runoff and allow rain to soak into the soil. Often the whole plant, root and all, is allowed to break down as a green manure, adding nutrition and organic matter and structure in the soil.
As it happens, we have a combination of hard clay soil and runoff in one of our garden areas, waterlogged in the winter and baked hard by the sun in the summer. So as well as growing daikon for eating, we have been putting these little ‘biodrills’ into action over the winter, ready for spring planting!