The USDA agent introduced himself as “Mr. Hash.” I worried I was having a flashback. I struggled to avoid asking, “You’re f#@*ing kidding me?”
This is a follow up to last month’s story Sorrow and Solace in Sichuan on 9/11.
I’d sent 140 seed accessions to Jelitto Perennial Seeds, following a 2001 Sichuan collecting trip. The shipment was approved by the Chinese authorities. Jelitto cleaned the seeds, got a German phytosanitary certificate, and sent a selected few seed packets to me, including one with cleaned seeds of peppercorn, purchased from an open-air Sichuan market. I sowed the seeds immediately. (My seeds didn’t germinate, but the seed pros in Germany succeeded, as ever.)
I had become fond of Sichuan food flavored with the tongue tingling, fiery-tasting prickly-ash tree, Zanthoxylum simulans. I’d also developed the long-lasting impression that every small Sichuan town smelled like stir-fried peppercorn and diesel exhaust.
Jelitto had labeled the packet with the common name, and though the Latin name is required, it mistakenly passed USDA inspection.

Original Jelitto-grown Sichuan peppercorn from 2001 seed collection. Georg Uebelhart photos.
A week or two after the seeds arrived in Louisville, I got a surprise visit from a new agent of the local USDA office. Jelitto was on good terms with the USDA. We didn’t stock any seed, and played by the rules, but I wondered at the time if the USDA thought our one-person office, marketing over 3000 varieties of perennial seeds across North America, looked suspicious.
The USDA agent introduced himself as Agent Hash.
I worried I was having a flashback. I struggled to avoid asking, “You’re f#@*ing kidding me?” I vaguely recall meeting an incarnation of Mr. Hash at the Atlanta Pop Festival on July 4th, 1970. Jimi Hendrix was about to come on stage. My memory is fuzzy, though I remember a sea of tie-dye.
There was no hidden stash for Agent Hash and, before he left, he told me proudly that he’d confiscated 50 LBS of Sichuan peppercorns in Louisville’s Asian markets earlier in the day. I was confused. I asked Agent Hash what the problem was with Sichaun peppercorns. He said sternly that it was in the citrus (Rutaceae) family.
I had presumed wrongly that the peppercorn was in the deadly nightshade (Solanaceae) family with tomatoes, potatoes, bell peppers, hot peppers and eggplants. The Sichuan peppercorns were banned from entry into the U.S. because of legitimate concerns about citrus canker being spread to oranges, lemons, limes, etc.

Poivre du Sichuan
I told Mr. Hash how much I loved Sichuan peppercorns. I followed him out the door and, like a curious boy, asked if I could see the confiscated goods from the raid. He popped open the trunk and I felt like I was watching the end to an episode of America’s Most Wanted.
Agent Hash calmly assured me that the Asian markets would be restocked the next week in the continuing culinary cat and mouse game.
For the next three years, until the ban was lifted, I pleaded in Chinese restaurants for my stir fry to be flavored with hua jiao (the Chinese name). My question always raised a red flag. Kitchen doors opened and eyes would appear, and I was told the Sichuan spice was not available. The answer was always the same—unless I was with Asian friends.
I could have been Agent Hash in disguise.
The Feds eventually lifted the peppercorn ban in 2004, when it became clear they were fighting a losing battle. They offered a fix: the seed pods could be treated by exporters for 20 minutes at 140 degrees in order to eliminate any chance of citrus canker.
I’m working up a list of vegetable, annual and perennial flowers to sow early next year. I’ve already sown seeds of chokeberry and bottlebrush buckeye. I sowed them in beds outdoors. One year I would like to try growing seeds of the Sichuan peppercorn again and also the American relative—toothache tree— Zanthoxylum americanum.
If I succeed, I will happily share my end-of-the alphabet, botanic booty with Mr. Hash, or a cooked meal, but I haven’t seen him since.
In addition to Zanthoxylum germination fantasies, I now enjoy cooking with Sichuan peppercorns.
Are you tempted?
You should sow seeds of Zanthoxylum outdoors in the fall to allow a warm period, followed by the natural temperature rhythms of the cold winter to break down germination inhibitors. If you’re lucky, germination may proceed as spring is rolled out.
You can find cooking recipes online, but I wing it with my stir fry, lending it a bit of southern flair. Throw peppercorns into a mix with olive oil and minced garlic, then add a vegetable medley of green beans, okra, corn, bell peppers, sun-dried tomato bruschetta plus pieces of cooked chicken or whatever else comes to mind. Touch it up with black pepper, salt, cumin, and turmeric, then smother a plate of wild rice with the stir fry.
You’re still not convinced?
Trust me on this next one.
I’ve got an addictive alternative: Peanuts flavored with Sichuan peppercorns.
Tell your friends you heard it first on the Garden Rant.
I have a packet (how come it was so easy to get in the uk?!). Thanks for the recipe suggestion! Xx
Thanks, Anne. No idea, really. Perhaps it’s because the UK has little, if any, citrus production? It’s a marvelous flavoring. And the spicy peanuts…
Could be. I think no commercial citrus here.
Afraid I am a bit of a wimp when it comes to spicy heat but I would grow the plant just for it’s gorgeous lacy foliage.
A mouthwatering rant!
There has been concern of carcinogenic effects of these plants
Thanks you, Victoria. Yes, I’d heard this and also that one species, perhaps others, may have anti-cancer properties.
Allen, regarding your growing plans for next year, I have several chokeberry bushes (Aronia arbutifolia Brilliantissima) with lots of little ones growing in the area. Perhaps these were spread by seeds in the dropped berries? If your seeds don’t take, I could dig one out for you…
Jack, thanks for your very kind offer. I’ve found a local source. If that falls through, I’ll get in touch.
Agent Hash was harshing some genuine good vibrations. It’s been determined that the numbing sensation of Sichuan peppercorns is a result of a measurable 50Hz frequency buzz it generates in your tongue and lips, the 麻 or ma’ of 麻辣 or ma’la (numbing/spicy). 麻辣 is the combination of prickly ash and chilis that gives Sichuan food its unique flavor.
Great article, Allen. Very informative.
Plants of Z. simulans are pretty consistently available to purchase in the U.S., but according to pretty much all of the literature, it is Z. bungeanum that is the primary source of the spice known in china as hua jiao. Z. armatum is also said to be cultivated for this purpose. Meanwhile, Z. simulans (called ye hua jiao, according to the Flora of China) is only widely cited as a source of the spice in Western literature. Unfortunately, I haven’t found a source for Z. bungeanum plants in this country, but I will say that the fruit of home-grown Z. simulans is much brighter, fresher, more citrusy and complex in flavor than the dried and probably heat-treated commercial article. Species in the genus are generally considered to be dioecious, and nurseries selling seedlings sometimes warn that a male and female plant is required for fruit (seedlings offered for sale are usually unsexed), but I have witnessed multiple isolated plants of Z. simulans fruiting heavily.
Stefan, this is wonderful information. Thank you so much. I presume, from what you’ve uncovered, that both Z. simulans, Z. armatum and Z. bungeanum are all grown for spice, but the connoisseurs might prefer Z. bungeanum. I have found, with whatever is being sold now—presumably heat-treated—that it lacks the firepower of untreated peppercorn. The spicy peanuts are lovely—a little heat but not overwhelming.
Actually, I have found no reports whatsoever of Z. simulans being grown for use as a spice in China (the Chinese being the only real connoisseurs in this case, of course!), but there is no indication of a reason. I have not found any documentation related to qualitative differences or any other sort of comparison between Z. simulans and either Z. bungeanum or Z. armatum–Z. simulans simply seems to be ignored by non-botanical Chinese literature about the spice. I suspect there is more to the story to uncover, but why there is such a large disconnect between what is said in the West and what is known in China is more than a bit of a mystery. Maybe the fact that both species were once called Z. bungei (Z. simulans being the Z. bungei of Planchon and Z. bungeanum being the Z. bungei of Hance) has something to do with it; that sort of quantum taxonomic entanglement might have resulted in the culinary/economic properties of one species becoming mistakenly attributed to the other.