Soak your leafy greens in ice-cold water, they say. It’ll make them plump and crisp, they say. But I’m here to tell you: Please do the exact opposite. Soak your sad, droopy greens in hot—not cool, definitely not cold—water and watch them resurrect like a time-lapse video in reverse.
Try it for yourself. Fill a large bowl with very hot tap water (around 120°F) and plunge your wilted greens. Let them soak for 10–30 minutes, then drain. Wrap the leaves in a damp towel and chill before using (or if you need them immediately, cool them down in ice water). They’ll be perkier than a Pomeranian with a plushie.
I first encountered this technique in Tracie McMillan’s remarkable book The American Way of Eating: Undercover at Walmart, Applebee’s, Farm Fields and the Dinner Table. As the title indicates, McMillan tries to understand the American food system from the inside out. First up: She started working at Walmart. On her second day in the produce department, she learns all about crisping. The internal training video instructs to trim and discard the woody ends of any leafy greens, then soak them in warm water before draining, labeling, and moving it into a commercial cooler, ready to be stacked on shelves.
If it’s good enough for Walmart, which I assume has put in countless money and time toward maximizing efficiency, it’s good enough for me.
This technique shows up in other places too. Florists have long used warm water to revive wilting flowers. Whether it’s a rose stem or radicchio head, the theory is that warm water opens up the cell walls more efficiently, allowing the delicate produce to absorb more liquid, more quickly. Modernist Cuisine, the research kitchen that puts out award-winning cookbooks, talks about heat shocking—soaking fruits and vegetables in very warm water—as an organic, effective way to preserve color, slow down wilting, and increase lifespan.
It’s become my go-to for endless leafy things. Soft herbs like cilantro, parsley, and basil. Salad lettuces like romaine, iceberg, and radicchio. Sturdier greens such as spinach, Swiss chard, and kale. Each has emerged, revived and invigorated, from the depths of the water like a character in a James Bond movie.