The dark days of winter are no time for fairweather friends – you need reliable, low-maintenance stalwarts to keep your greenhouse cropping through to spring
Last September I sowed the seeds of a wintertime get-together for some old friends, whose company I knew I would relish from the darkening days of late autumn right through to the lengthening days of spring.
These loyal and trusted stalwarts have been at my side through the deepest winter days, helping me leapfrog the winter solstice with ease; they never ever let me down. If you’re wondering just how I’ve acquired friends with such staying power, I have a confession: those seeds sown back in autumn were real ones.
Oriental greens ‘Mizuna’ and ‘Mispoona’, Japanese green ‘Komatsuna’, Chinese salad cabbage ‘Bekana’ and mustard green ‘Dragon’s Tongue’ are among the invitees to my winter gathering’s 18-strong guest list (I could easily have doubled it). Their names explain why they belong to a group of leafy vegetables known as Asian or oriental vegetables/greens, alongside a distinctive, fiery-leaved clan known as mustard greens. They come in every hue of green, as well as purple, red, yellow and gold. For brevity I’ll refer to both as ‘orientals’, as they all have their roots in the Far East. Decent seed catalogues all list some orientals, some having looser definitions than others.
My urge to bring together these much-loved leafy old muckers was in part because I’d missed them (through forgetting to order seeds at the right time…), and partly because they’re incredibly easy-going greenhouse guests, requiring zero warmth or meals and only occasional sips of water, but mostly because they keep the crunch-crunch-crunch of fresh, flavoursome, nutritious and packaging-free salads going from late autumn right through to spring (you can also use them in stir-fries and other dishes). Orientals thrive in the cooling days of autumn, grow steadily through winter’s gloom, before bursting into bloom come warming spring.
Their star quality is that they do all of this powered only by free and non-polluting renewable sunshine; don’t even think about putting them under resource- and energy-demanding artificial lights – they don’t need them. Orientals are winter’s ultimate, low-fuss, high-yield winners, which is why I love having them around.
The only times they can’t offer me fresh snippings is when the inside of the greenhouse glass resembles a skating rink; during hard, pot-penetrating frosts, orientals sag and sulk, turn dark, and look for all the world like goners – but they’re not (mine recently flopped when pots-frozen-solid night frost hit -7ºC, but soon bounced back). Following a thaw, they quickly revive, and carry on and on and on cropping. To secure non-stop salad supplies, I move pots or trays of orientals to a cool, frost-free indoor windowsill before temperatures plummet.
Growing orientals is a cinch. Although many are suited to sowing from late summer into autumn, most can be sown year-round. Spring- and high-summer-sown orientals will tend to bolt quickly and produce flowers as temperatures rise, so in the hotter months they’re best treated as fast-growing microgreens (although these always feel like a waste of full salad potential to me), or as cut-and-come-again mixed leaves, for which you can buy seed blends.
Seeds of orientals are easy to handle, and you only need a pinch to get plenty of young plants. As a general rule, the more room you allow between plants, the bigger – and leafier – they will get. From late summer sowings you can expect fresh pickings in as little as three to four weeks.
If you’re just getting to know Asian/oriental and mustard greens, Real Seeds has one of the widest selections, alongside comprehensive growing instructions, including handy sowing calendars. For a deep gardening dive into my favourite oriental companions, and so much more, grab yourself a copy of Oriental Vegetables by the esteemed writer Joy Larkcom, whose travels, research and trials introduced many of these crops to our gardens, plots and plates (the book is out of print, but pre-loved copies abound).
My winter companions were sown in small pots and germinated in the living room – keep an eye on them, as some come up in days and need to go straight into the greenhouse to avoid them turning pale and leggy. I potted them on into 17cm pots of spent peat-free compost, reinvigorated with my own wormpost. Apart from light watering to settle them in, they’re only given sips of water (they don’t need feeding) – and then only when they show signs of wilting; keeping them dry, and opening the greenhouse vents fully, staves off winter moulds. Check for slugs after dark, including underneath pots and trays.
Harvesting is easy, but you need to get the hang of it. There are two approaches: cutting whole plants or selectively snipping a mixture of leaves. Pak choi forms a solid, distinct plant and is worth cutting whole, while ‘Mizuna’ produces a mass of feathery foliage which crops over several months. I prefer to gather a good handful of mixed leaves on each pass, judging how much to take from each plant.
Less feisty orientals, such as ‘Golden Frills’, an intriguing, frilly-leaved hybrid between kale and mustard, are slow, plodding growers, so avoid giving them too harsh a trim, especially in midwinter when daylight is scarce. Whole plants can be harvested with a knife, but scissors are ideal for judicious snipping; take everything you cut, and avoid leaving fragments behind which could go mouldy.
Lengthening days mean steadily increasing growth and an endless supply of tasty leaves; watering can keep step with warming days. When spring proper arrives, orientals bolt into growth as they begin to bloom, producing tall shoots carrying their heady, sweet-scented yellow flowers. The buds and flowers are edible, but don’t gobble them all – they’re also a source of pollen and nectar for adult hoverflies and other overwintered insects. A few pots of blooming orientals stood outside on spring days become an instant insect refuelling station.
If orientals become the kind of reliable friends you can’t garden without, you can leave some to produce their long thin green seed-pods, which turn brown as they ripen, and sow your own (Real Seeds champions saving your own seed with free, detailed advice on its website).
Spring is a time for fond farewells to those orientals that have kept me happily crunching away through winter. I’ll rely on more fleeting friends to provide me with handfuls of baby leaves through the hotter months, but I can’t wait for late summer to come around, when I can sow some more familiar faces – and some new ones.
Text and images © John Walker
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