"Habit: Annual, perennial herb, rhizomed or stoloned. Stem: prostrate to erect, ribbed or +- so or not, glabrous or hairy, generally with adventitious roots. Leaf: cauline, alternate, petioled or not; ocrea papery, rarely +- leaf-like, opaque, persistent or disintegrating, glabrous to variously hairy; blade lanceolate or ovate to hastate or sagittate, entire. Inflorescence: axillary, terminal, generally spike-like; flowers 1--14; peduncle present, pedicels present [or 0]. Flower: bisexual or functionally +- unisexual, base not stalk-like; perianth not or +- enlarging, bell-shaped (urn-shaped, rotate), glabrous, gland-dotted or not, green-white, white, pink, or red; perianth parts 4--5, fused 1/4--2/3, outer 2 > inner 2 or 3; stamens 5--8, filaments free, cylindric, thread-like, glabrous, outer fused to perianth tube or not, anthers elliptic to ovate, yellow, pink, or red; styles 2--3, erect to reflexed, free or fused, stigmas head-like. Fruit: included or exserted, brown or dark-brown to black, not winged, discoid, lens-shaped, or 3-angled. Seed: embryo curved."
Species In Genus: "+- 100 species: +- worldwide. Etymology: (Latin: persica, peach, aria, pertaining to; from resemblance of leaves of some species to those of peach)" [Jepson]

Comment: "There is a close relationship between Persicaria, Bistorta and Polygonum." [Personal Observation]

Local Species;

  1. Persicaria amphibia var emersa - water smartweed [E-flora][TSFTK]
  2. Persicaria hydropiper - Marshpepper smartweed [E-flora][PCBC]
  3. Persicaria hydropiperoides - Small water-pepper [E-flora][PCBC]
  4. Persicaria lapathifolia - Willow weed [E-flora][PCBC][TSFTK]
  5. Persicaria maculosa - lady's-thumb [E-flora][PCBC]
  6. Persicaria minor - Asian knotweed [E-flora]
  7. Persicaria punctata - Small dotted smartweed [E-flora][PCBC]
  8. Persicaria wallichii - Himalayan knotweed [E-flora][PCBC]


Persicaria amphibia


Persicaria hydropiper - Marshpepper Smartweed



Persicaria hydropiperoides - Small water-pepper


Persicaria lapathifolia - Willow Weed


Persicaria maculosa - Lady's-thumb


Persicaria minor - Asian Knotweed

Researching the relationship to Polygonum odoratum

  • Polygonum odoratum (Persicaria odorata (Lour.) Sojak.) - Vietnamese Mint/Coriander
    • Taxonomy: "Persicaria odorata (Lour.) Soják [This species should not be confused with Polygonatum odoratum (Mill.) Druce, angular Solomon's seal, a Eurasian herb of the lily family, that is sometimes cultivated as an ornamental.] Potter et al. (1993) state that the identity of the plant known as rau ram in North America is somewhat uncertain, and they imply that it may be the same species that has been identified as Polygonum minus Hud." [Small CH]
    • Location and Climate Range: "The plant is cultivated in Australia for a number of years. Literature searches reveal very little about the origin, but most probably introduced into Australia by immigrants from South-East Asia. Polygonum minus Huds is spread across South-East Asia, where the taxonomy is very similar to P. odoratum. Both varieties are very similar, except P. odoratum has a broader leaf. The chemotaxonomy of both varieties is very similar [52]." [Hunter EO]
    • Food Use: "The baby leaves have a pungent coriander flavor, while the mature leaves have a hot, pungent, peppery flavor that can dominate. Use as a fresh leaf condiment, at the end of cooking. Important in Asian cuisane, this herb is used in noodle soups (pho) from vegetables, seafood, or meat, and also in stir-fried meat and vegetable dishes." [mcvicar GH]
    • Medicinal Use: "Medicinally, it is drunk as an infusion to ease indigestion. To get rid of dandruff, the leaves are pounded to extract the kesum oil, which is then massaged into the scalp prior to washing." [mcvicar GH]
    • Economic and Potential Uses: "As a source of natural aliphatic aldehydes, as a flvouring material and for natural aldehydic notes in perfumery." [Hunter EO]
    • Part of the Plant Containing Oil: "Leaves and to a lessor extent, the stems. Yields of P. odoratum oil in North-East Victoria are higher than yields in Northern Malaysia, which is probably due to the milder climate in Victoria [53]." [Hunter EO]
    • Method of Extraction: Steam distillation [Hunter EO]
    • Chemical Constituents: "1-decanol (alcohol C10) 3-4.0%, 1-dodecanol (alcohol C12) 5- 12.0%, decanal (aldehyde C10) 20-25.0% and dodecanal (aldehyde C12) 45-50.0% [54]." [Hunter EO]
    • Cultivation: "Grow in ordinary soil in sun or part shade. Makes a good container plant where it can be kept in bounds. Take rooted cuttings to overwinter in colder climates." [NAH Orr]


Persicaria punctata - Small dotted smartweed


Persicaria wallichii - Himalayan knotweed


Pungent Compounds

"Polygodial is the major component of the medicinal plants Polygonum hydropiper, P. minus, and P. punctatum var. punctatum (Polygonaceae). It is noteworthy that some ferns, such as Blechnum fluviatile collected in New Zealand and the Argentinean Thelypteris hispidula, elaborate the pungent component, polygodial (548), together with related drimanes (77, 761)." [Asakawa CCB]

"5,7-Dihydroxychromone, isolated from P. persicaria and P. lapathifolium, was found to exhibit antigermination activity.13,14" [Cutler BANPP]

Other Species


Page last modified on March 15, 2017, at 01:46 AM