
Persicaria odorata or Vietnamese coriander. Check your farmers market.
What’s this herb? I said as I picked up a bundle of greens I’d never seen. “Good Herb!” the older woman told me in her thick Southeast Asian accent. She motioned for me to taste some. I picked up a leaf, gave it a little crunch to release any aroma and smelled: it was wonderful, a little like cilantro crossed with epazote. “Um, what is it?” I said. The woman shrugged. She didn’t give a name for it. Now I was interested.
Something in the stem set off a flag in my mind, I’d seen the branchy pattern with a red base where the leaf shoots come out somewhere, and recently. It kind of looks like Japanese knotweed shoots, which I was still seeing come up at the farm in areas that get mowed over the summer. Not red enough for knotweed though, this was different.

One of the many smartweeds that are supposed to grow in Minnesota. It has no taste, and no odor, just a pain if you have a garden.
Waterpepper, that was it. Some of my friends had posted about using it online. But, I know that waterpepper is supposed to be a chili substitute, not aromatic. They looked so similar, I just didn’t understand. Either way, it smelled delicious, she was selling it, and I needed to eat it.
“How do you use it?” I asked. “You cook chicken, you eat when roast chicken”, she said. She mimed putting a leaf on top of an invisible chicken niblet in her hand and eating it.
I wanted to spout off all the questions:
“So do I apply the herb directly to the meat and then cook it?” “Is it sprinkled on as a garnish afterwords?” “Does the aroma take time to penetrate the meat?” “Is it dry-able?” “Is it tossed in the roasting pan literally to perfume the meat?” Should I chop it, bruise it, cook it like a bay leaf and discard it?” “You can’t just tell me you don’t know what it is when it smells amazing and you are selling it!” &$^#!

Harvested the same day as the similar-looking smartweed above. Note the Vietnamese coriander is not showing flowers, it’s also larger in stature.
I smiled, nodded and handed her my 3 dollars. She replied with: “You no know how to use, maybe you no buy.” I gave her a half-annoyed smile and told her I’d be back next week for the malabar spinach, which they usually had but were out of, and left.
Preserving Culinary Traditions
I thought about the farmer a number of times in the next few days-our conversation grew on me. I thought it was so special that they would try to sell something knowing that the vastly white/caucasion farmer’s market shoppers will walk right by it looking for things they’re comfortable with, and they didn’t even have a name to describe it for customers. I wondered, would their children carry on the tradition of using this plant? Their children whose English will be indestinguishable from mine, a native Minnesotan, after they grow up? If they don’t have a common name for the plant, is there a threat of it’s use being forgotten, at the very least by their family that live in the United States? How many food traditions have already been pushed to extinction because of our united melting pot?
Obviously I’m speculating a bit here, but many food traditions have already been lost from other cultures, and if we don’t seek them out and work to preserve them, they will be lost. Native American culinary traditions are another example, and arguably more endangered.
3 Types of Smartweed, 3 Different Tastes
I got home, turned on the computer with a few greens in my lap and got to work. Since the first thing I thought it could be was a type of smartweed, I looked at those first, nada. All I could find was descriptions of different spicy weeds and other tasteless ones I’d seen locally, but it did tell me the genus name: Persicaria. The next thing I did was search using Persicaria along with Asian cuisine. Bingo. Persicaria odorata, Vietnamese coriander.
The Skinny
From my experience wild smartweeds with red flowers (P. hydropiperoides) will be tasteless, those with drooping green flowers (P. hydropiper) will taste like hot chili. Both like the same habitat, and they like to grow together in damp an disturbed areas and come up during the late summer, I started picking them in the middle of August in Minnesota.
The Vietnamese coriander has completely different flowers, (They’re white and they actually look like flowers) and is not wild-growing, from what I can tell. Since I know the farmers don’t use green houses, to me it follows that it could be cultivated in the Midwest, and with having seen the aggressiveness that smartweeds have, it probably isn’t going to be difficult.
Channeling the Hmong woman I spoke to, I futsed around with the Odorata and tried it a few different ways. Every way I tried it, I loved it. It’s a strong herb, and it’ll take over if given the chance, but overall a great addition to the summer aromatic arsenal. I’ll tell you, my mouth is watering imagining it next to a bowl of broth or pho along with some fresh mint and cilantro to mix in with the noodles right before they hit your mouth for blasts of aroma. Next time I’m making soup.
The first way I served it was really simple: a garnish for some flank steak and a hash of vegetables from the garden and lobster mushrooms. You take a bite of meat, put a leaf on it, eat it, with a dash of lime, maybe. This is just an example, if you want to see the formal recipe, there’s a link below.
Oh, you don’t need to worry about if maybe it’s nameless and incommunicable! Rau ram is the Vietnamese name (if you touch up the vowels), various other languages have their own, I don’t know the Hmong. Loss of culinary cultural tradition is for real but I don’t know that you need to direct your concern at this particular herb. Looks from here whoever goes into the next generation of the kitchen will know its name and use, it’s commonly grown (pots in water trays on the back doorstep of the Vietnamese restaurants) and also sold as you saw. Unless users of it think it’s at risk?
Do grow some, it’s delicious, vigorous, and best of all a perennial. I don’t grow actual cilantro anymore because it bolts while your back is turned. (Not that they’re interchangeable, but, eh, it’s tastier than that bolted cilantro.)
Have you seen it grown outdoors? Don’t know how you’d overwinter it in the Midwest, it’s a frost-tender from a warmer climate. Hm, roots that are under some water (it tolerates/likes that) might be protected if that doesn’t freeze solid.
In Oz we call this Vietnamese mint
I just made the chicken dish that lady was talking about. You just need to mix the following ingredients: steamed shredded chicken (white or dark mix), chopped rau ram (destemmed), lime, salt, and chili peppers (optional).
Thanks Chi.
in Malaysia we call it daun kesum. We use interchangeably with cilantro. Its a relative of mint and thrives in 1/2 sun and wetter earth. Its amazing with lemongrass, tamarind, galangal etc all Southeast Asian herbs. I also like to add it in my Vietnamese rice paper rolls!
Theza, that is some great information, I really like this herb, and others from the genus Persicaria. I’m curious, do you use waterpepper or Persicaria hydropiper? It’s spicy hot like horseradish.
Hi!
Funny and good to know!
By any chances, do you know if we can eat it in large quantities without health problem? I mean, like basilica or spinach?
Because it is so easy to grow, it is tempting to eat “too much” of it, is it possible to eat “too much” of it?
Thank you 🙂
My curiousity has been SPARKED!
I did a few searches looking for seed, no avail– any ideas?
I just started your book, excited about it, thank you!