For Sun Lixin, a 68-year-old Beijing native who has spent more than half a century in the kitchen, few aromas are unfamiliar. Each spring, there is a particular one he waits for: the sharp, unmistakable scent of fresh Chinese toon shoots, rising suddenly and vividly with the season.
In his memory, that smell is tied to life in old Beijing courtyard homes. As late spring arrived, toon trees in the yard would push out purplish-red buds. Families would use a long pole with a wire hook to pull down the tender shoots from high branches.
"You have to pick them when they still have that reddish color — just right," Sun recalled. "A few days later, they turn tough and can't be used."
This precise sense of timing reflects a deeply rooted culinary principle in China: eating with the seasons. The moment is closely linked to Grain Rain (gu yu), the final solar term of spring, which starts on Monday, when rising temperatures and rainfall bring rapid plant growth. It is also the brief window when Chinese toon — often called the "vegetable from a tree" — is at its most tender and flavorful.
Known as Toona sinensis, Chinese toon is famous for its strong, distinctive aroma. Some prize it as a seasonal delicacy, while others find it overpowering, but for many Chinese diners, spring feels incomplete without it. Its season lasts barely a couple of weeks, after which the leaves quickly become fibrous and bitter.
For Sun, the appeal of toon is inseparable from his childhood memory. Growing up in a time of modest means, he recalls how it elevated even the simplest meals. "If there was no cucumber or cabbage, we'd pick some toon, chop it finely, and mix it into hot noodles," he said. "The aroma was incredible."
As the weather warmed, sesame paste noodles became another staple. Thinned sesame paste, seasoned lightly and paired with a drizzle of Sichuan peppercorn oil, was topped with chopped toon. "The fragrance blends together — it's very refreshing in summer," Sun said.
Another favorite was xiangchun yu, or toon fish, in which the shoots were coated in a light batter and fried until crisp. As they sizzled in the hot oil, the leaves unfurled, resembling small swimming fish. Simple as it was, the dish brought a sense of occasion to the table.
Today, Chinese toon has moved beyond courtyard kitchens into restaurants across the country. For chefs, it offers creative possibilities as a bold flavoring ingredient — paired with fish, seafood or even incorporated into sauces. But its defining quality remains unchanged: freshness.
"Once the season passes, you can't really use it anymore," Sun noted.
Despite its evolving role in modern cuisine, Sun believes the true significance of toon lies beyond technique. Its intense aroma, he said, carries memories.
Unlike most ingredients, which were bought from markets, toon was something families grew and picked themselves. A plate of toon was not just a seasonal dish, but a reminder of home and connection.
"When you smell it, you think of the past — of the old courtyard, of family, of people who are no longer there," he said. "Food has warmth. It carries emotion."
As Grain Rain passes and summer approaches, the appearance of Chinese toon marks the closing note of spring. To eat it is not only to enjoy its brief, vivid flavor, but also to take part in a quiet ritual — one that captures the essence of the season, and offers a final, lingering farewell.