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Persicaria tinctoria; photograph Daderot, CC0, via Wikimedia Commons CC0Daderot, CC0, via Wikimedia Commons

Persicaria tinctoria (Aiton) Spach

Polygonaceae · China South-Central, China Southeast +1

Cited as Kew's World Checklist cites it, Persicaria tinctoria (Aiton) Spach: GBIF's backbone key for this page carries the name with another author, (Aiton) H.Gross.

No habitat climate
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Persicaria tinctoria, photograph Udo Schröter, CC BY-SA 3.0, via Wikimedia CommonsPersicaria tinctoria, photograph Dinkum, CC BY-SA 3.0, via Wikimedia CommonsPersicaria tinctoria, photograph Krzysztof Golik, CC BY-SA 4.0, via Wikimedia CommonsPersicaria tinctoria, photograph Krzysztof Golik, CC BY-SA 4.0, via Wikimedia CommonsPersicaria tinctoria, photograph 小石川人晃, CC BY-SA 4.0, via Wikimedia CommonsPersicaria tinctoria, photograph Kenlo Nasahara, CC BY-SA 4.0, via Wikimedia Commons 12 photographs ›

Summary

Persicaria tinctoria is a species of flowering plant in the buckwheat family. Common names include Chinese indigo, Japanese indigo and dyer's knotweed. It is native to Southern China and Vietnam, and has been introduced to other parts of China, as well as Germany, Japan, Korea, Tibet, North and South Caucasus, parts of the Russian Far-East, and Ukraine.

Quoted from Wikipedia, "Persicaria tinctoria", CC BY-SA 4.0.

Cultivation

Nothing derived: no habitat climate for this species.

Climate across the habitat

No habitat climate can be derived: 48 in-range records, none placed to within 10 km. 48 of the 48 in-range records are placed to worse than 10 km, or to no stated accuracy and fewer than three decimals or by something other than a person's observation, and cannot place a climate cell, though they count for the map and its marker.

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing.
Openly licensed records inside the range, framed on where they fall.
NativeChina South-Central, China Southeast, Vietnam · introduced: Germany, Ukraine, Kuril Is., Primorye, Sakhalin, North Caucasus, Transcaucasus, Hainan, Manchuria, China North-Central, Tibet, Japan, Korea, Nansei-shoto, Myanmar · regions are the level-3 units of the World Geographical Scheme for Recording Plant Distributions, as Kew's World Checklist records ranges, some under historical names such as Yugoslavia or Czechoslovakia (how).
Map marker25.133, 105.4 · in the densest population, 31 records (65% of those in range)
Kew's description“annual” · “temperate” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 48 georeferenced records inside the native range; the map shows only the 26 openly licensed ones, which alone would put the marker 174 km away. 63 records outside the WCVP native range not used. No climate across the range is derived for this species. 48 in-range records are placed to worse than 10 km, or with no stated accuracy (admitted only as a person's observation to three decimals), and stay on the map but off the climate.
How this section is made
The map marker: the openly licensed record nearest the middle of the densest 1° population inside the densest 4° block of the 48 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Persicaria tinctoria, photograph 1did not loadPersicaria tinctoria, photograph 2did not loadPersicaria tinctoria, photograph 3did not loadPersicaria tinctoria, photograph 4did not loadPersicaria tinctoria, photograph 5did not loadPersicaria tinctoria, photograph 6did not load

Photographs: Udo Schröter, CC BY-SA 3.0, via Wikimedia Commons; Dinkum, CC BY-SA 3.0, via Wikimedia Commons; Krzysztof Golik, CC BY-SA 4.0, via Wikimedia Commons (2); 小石川人晃, CC BY-SA 4.0, via Wikimedia Commons; Kenlo Nasahara, CC BY-SA 4.0, via Wikimedia Commons.

Other Persicaria 42 in the reference

Persicaria acuminata Persicaria acuminata Tapertip Smartweed Photo: CC BY, Seba FernándezPersicaria amphibia Persicaria amphibia Amphibious bistort Photo: CC BY, Sandy WolkenbergPersicaria arifolia Persicaria arifolia Halberd-leaved tearthumb Photo: CC BY-SA, V. Ross JohnsonPersicaria attenuata Persicaria attenuata Watersmart Weed Photo: CC0, author not statedPersicaria barbata Persicaria barbata Bearded knotweed Photo: CC BY, chiuluanPersicaria biconvexa Persicaria biconvexa Polygonaceae Photo: CC0, 葉子Persicaria bicornis Persicaria bicornis Pink smartweed Photo: CC0, author not statedPersicaria capitata Persicaria capitata Pinkhead smartweed Photo: CC0, author not statedPersicaria chinensis Persicaria chinensis Chinese knotweed Photo: CC BY, Ben CostamagnaPersicaria decipiens Persicaria decipiens Slender knotweed Photo: CC BY, Duarte FradePersicaria dichotoma Persicaria dichotoma Polygonaceae Photo: CC BY, 如此甚好Persicaria extremiorientalis Persicaria extremiorientalis Far-Eastern smartweed Photo: CC BY, Heather Mazzaccaro all 43 ›

Names & registers

Also known as Ampelygonum tinctorium; Pogalis tinctoria; Polygonum tinctorium. (GBIF Backbone)

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Polygonaceae
Described by
(Aiton) Spach
Native to
China South-Central, China Southeast, Vietnam
Wild records
48 in range · 26 open

Every figure here is derived from public data by a stated rule and names its source; nothing about this species is written for its page by a person or by AI, apart from the marked, credited quotations. How →

Where this page came from built 2026-10-22
GBIF species record gbif.species answeredasked 2026-10-22GBIF's key 4032517 is Persicaria tinctoria (Aiton) H.Gross; the page links Kew's Persicaria tinctoria (Aiton) Spach, and the name is cited as Kew cites it
GBIF synonyms gbif.synonyms answeredasked 2026-10-22
GBIF common names gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22
WCVP native range wcvp.distribution answeredas of 2026-06-04
GBIF occurrence records gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 7 records within 1 km of a botanic garden, herbarium or zoo left out (6 at a botanic garden or arboretum, 1 at a zoo; Wikidata's list)
Habitat climate climate nothing to reportasked 2026-10-2248 in-range records, none placed to within 10 km
Wikidata wikidata answeredasked 2026-10-22IPNI and POWO linked by Kew's number for Persicaria tinctoria H.Gross (the item's: IPNI 695176-1, POWO 60455325-2)
Wikipedia wikipedia answeredasked 2026-10-22
iNaturalist photographs, wild inat.photos.wild nothing to reportasked 2026-10-22from iNaturalist's open data of 2026-09-27: research-grade observations with an open-licence photograph, the 24 whose photographs iNaturalist received last (the open data holds no votes); filled 2026-10-22
iNaturalist photographs, cultivated inat.photos.cultivated not asked
GBIF media gbif.media nothing to reportasked 2026-10-22
Wikimedia Commons commons answeredasked 2026-10-22
OpenAlex papers openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshot

Every source is recorded as having answered, reported nothing, refused, failed, not been asked, or answered twice where one answer is taken (“not taken: two items answered”), and, for a source asked when this page was built, when: the figures are as the source held them that day; a source read from a file (Kew's World Checklist, a GBIF download) says "as of" the file's day instead; a row carried from an earlier build of the page names that build instead. Only “nothing to report” is ever shown as an absence. Records came from 36 datasets via GBIF.org; each carries its own licence.

Cultifolio

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