Japanese Winter Greens: A Primer

Mizuna enjoying a bit of winter sun.

Look for Japanese Winter Vegetables: A Primer, Part Two, here!

People are often surprised to find out that the Tokyo farm where I help out is busy with winter vegetables. "But it's too cold," they say, and their surprise increases as I start to list the variety of things currently in the field: daikon, kabu, and all the leafy greens I have come to know and adore since arriving here five years ago. Many of these vegetables thrive in these conditions -  cold, frosty nights and bright, sunny days - and don't mind the long stints without rain so typical of this season.

The cold weather, in fact, is beneficial. "Komatsuna is sweeter and darker after a frost," said C-chan the other morning as we worked preparing the days harvest for shipment. And indeed, the plants looked particularly vivid and delicious as they lay on the wooden table. Like kale and brussel sprouts, komatsuna produces more sugars during a frost in an effort to protect itself from the cold. Water moves to the roots, which results in a greater concentration of sugars in the leaves. A brilliant survival tactic that makes for a delightful salad or soup!

Winter greens are by far my favorite Japanese vegetables. Their flavor, texture, nutrition, and colors make them hands-down winners in my book over almost anything the summer season brings. Raw in salad, blanched like shungiku, zipped into a stir-fry, or swirled into nabe (hot pot) or udon they surely will not disappoint.

Komatsuna leaf shortly before becoming salad.

Komatsuna is a Tokyo favorite that is most prevalent now in shops and at farmstands around the city. It is a wonderful green with a verdant leaf and a crunchy stem that goes well in salad or soup. (I just rough cut it into the bottom of the serving bowl and serve the soup on top. The quick cooking softens it just enough while also drawing out more color.)

Freshly harvested karashina.

Karashina (sometimes thrown in with mizuna in seed catalogs) comes in a wide variety of shapes and colors, but as its name implies - karashi (spicy)-na (leaf) - it has the softest of kicks. The farmers introduced me to it five years ago during my first winter, and its nutty flavor and lacy leaves made it an immediate favorite. Stems and all of this mustard family member are worth rough cutting into soup or salad. High in vitamins A and C as well as a nice assortment of minerals, karashina is as nutritious as it is pretty. It is also worth noting that traditional varieties of karashina resemble kale in appearance and texture, although not flavor.

Wasabina enjoying winter in the garden.

Wasabina, another spicy one, shares its name with Japan's most famous hot, green paste, but doesn't pack the same punch. (For that try some  nasturtiums - leaves as well as blooms - during the summer. Yowzers!) Usually harvested small, the softly serrated leaves sometimes have a bristly look to them. Ignore this and munch away raw in salad or slightly cooked in soup.

Mizuna, a classic nabe ingredient, can be found nearly year-round now in grocery stores, but is best during the winter months. Long, thin white stems topped with serrated green leaves, mizuna has a delicate, sweet taste perfect in salad or soup. In the field, mizuna grows thickly out from a central base stem. Before being broken up and prepared for the supermarket, plants can resemble haksai (chinese cabbage) in overall shape. If adding it to nabe, toss it in at absolutely the last minute. Too much cooking turns it to mush and it loses all its color, which is not any fun.

Next week: More winter greens and where to find the seeds!