Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide


Portulaca oleracea



Portulaca oleracea (purslane)


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Portulaca oleracea (purslane); shoot, with blooms.
TitleShoot with blooms
CaptionPortulaca oleracea (purslane); shoot, with blooms.
Copyright©Didier Descouens - CC BY-SA 3.0
Portulaca oleracea (purslane); shoot, with blooms.
Shoot with bloomsPortulaca oleracea (purslane); shoot, with blooms.©Didier Descouens - CC BY-SA 3.0
Portulaca oleracea (purslane); from a typical, open, disturbed habitat purslane grows rapidly, producing flowers, fruits and seeds within 6 weeks of germination.
CaptionPortulaca oleracea (purslane); from a typical, open, disturbed habitat purslane grows rapidly, producing flowers, fruits and seeds within 6 weeks of germination.
Copyright©S.D. Sawant
Portulaca oleracea (purslane); from a typical, open, disturbed habitat purslane grows rapidly, producing flowers, fruits and seeds within 6 weeks of germination.
PropagationPortulaca oleracea (purslane); from a typical, open, disturbed habitat purslane grows rapidly, producing flowers, fruits and seeds within 6 weeks of germination.©S.D. Sawant
Portulaca oleracea (purslane); 1, Granulate pattern; 2, stellate (S-undulate) pattern in P. oleracea.
TitleSeed patterns
CaptionPortulaca oleracea (purslane); 1, Granulate pattern; 2, stellate (S-undulate) pattern in P. oleracea.
Copyright©J.F. Matthews
Portulaca oleracea (purslane); 1, Granulate pattern; 2, stellate (S-undulate) pattern in P. oleracea.
Seed patternsPortulaca oleracea (purslane); 1, Granulate pattern; 2, stellate (S-undulate) pattern in P. oleracea.©J.F. Matthews
Portulaca oleracea (purslane); 3, Stellate (S-undulate) tuberculate pattern; 4, raised stellate (S-undulate) pattern without tubercles, in P. oleracea.
TitleSeed patterns
CaptionPortulaca oleracea (purslane); 3, Stellate (S-undulate) tuberculate pattern; 4, raised stellate (S-undulate) pattern without tubercles, in P. oleracea.
Copyright©J.F. Matthews
Portulaca oleracea (purslane); 3, Stellate (S-undulate) tuberculate pattern; 4, raised stellate (S-undulate) pattern without tubercles, in P. oleracea.
Seed patternsPortulaca oleracea (purslane); 3, Stellate (S-undulate) tuberculate pattern; 4, raised stellate (S-undulate) pattern without tubercles, in P. oleracea.©J.F. Matthews
Portulaca oleracea (purslane); 5, Raised stellate (S-undulate) pattern with incipient tubercles; 6, granulate pattern with tubercles of  P. oleracea.
TitleSeed patterns
CaptionPortulaca oleracea (purslane); 5, Raised stellate (S-undulate) pattern with incipient tubercles; 6, granulate pattern with tubercles of P. oleracea.
Copyright©J.F. Matthews
Portulaca oleracea (purslane); 5, Raised stellate (S-undulate) pattern with incipient tubercles; 6, granulate pattern with tubercles of  P. oleracea.
Seed patternsPortulaca oleracea (purslane); 5, Raised stellate (S-undulate) pattern with incipient tubercles; 6, granulate pattern with tubercles of P. oleracea. ©J.F. Matthews
Portulaca oleracea (purslane); 7, Raised stellate (S-undulate) pattern with definite tubercles; 8, root- tip squash showing 2n=26 in P. oleracea.
TitleSeed and root tip
CaptionPortulaca oleracea (purslane); 7, Raised stellate (S-undulate) pattern with definite tubercles; 8, root- tip squash showing 2n=26 in P. oleracea.
Copyright©J.F. Matthews
Portulaca oleracea (purslane); 7, Raised stellate (S-undulate) pattern with definite tubercles; 8, root- tip squash showing 2n=26 in P. oleracea.
Seed and root tipPortulaca oleracea (purslane); 7, Raised stellate (S-undulate) pattern with definite tubercles; 8, root- tip squash showing 2n=26 in P. oleracea.©J.F. Matthews
Portulaca oleracea (purslane); general habit, showing foliage and flowers.
CaptionPortulaca oleracea (purslane); general habit, showing foliage and flowers.
Copyright©A.R. Pittaway
Portulaca oleracea (purslane); general habit, showing foliage and flowers.
HabitPortulaca oleracea (purslane); general habit, showing foliage and flowers.©A.R. Pittaway
Close-up of foliage and flower; close-up of foliage and flowers.
TitleFoliage and flowers
CaptionClose-up of foliage and flower; close-up of foliage and flowers.
Copyright©A.R. Pittaway
Close-up of foliage and flower; close-up of foliage and flowers.
Foliage and flowersClose-up of foliage and flower; close-up of foliage and flowers.©A.R. Pittaway
Portulaca oleracea (purslane); flowering habit.
CaptionPortulaca oleracea (purslane); flowering habit.
Copyright©Chris Parker/Bristol, UK
Portulaca oleracea (purslane); flowering habit.
HabitPortulaca oleracea (purslane); flowering habit.©Chris Parker/Bristol, UK


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Preferred Scientific Name

  • Portulaca oleracea Linnaeus 1753

Preferred Common Name

  • purslane

Other Scientific Names

  • Portulaca diptera Zippelius ex. Spanoghe
  • Portulaca fosbergii Poelln.
  • Portulaca marginata HBK
  • Portulaca neglecta MacKenzie & Bush
  • Portulaca parviflora Haw.
  • Portulaca retusa Engelmann
  • Portulaca sativa Haw.

International Common Names

  • English: duckweed; garden purslane; little-hogweed; pursley; pusley; pussley; wild portulaca
  • Spanish: verdolaga
  • French: courpier; pourcellaine; pourpie potager; pourpier
  • Portuguese: beldroega-comum

Local Common Names

  • China: ma chi xian; ma chia xian
  • Germany: Portulak, Gelber
  • Italy: erba porcellana; porcellana; porcellana comune
  • Japan: Suberi-hiyu
  • Netherlands: postelein, wilde
  • Sweden: portulak, vanlig

EPPO code

  • POROL (Portulaca oleracea)

Taxonomic Tree

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  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Caryophyllales
  •                         Family: Portulacaceae
  •                             Genus: Portulaca
  •                                 Species: Portulaca oleracea

Notes on Taxonomy and Nomenclature

Top of page Portulaca oleracea (purslane) is an ancient, cosmopolitan species in which self fertilization is the rule. Hence, local populations exist which reflect variable morphological and physiological traits expressed as part of the genome of that population. However, purslane has not been split into a series of microspecies.

The two most recent comprehensive monographs, Legrand (1962) and Geesink (1969) provide, respectively, only three and two names as synonyms. Gorske et al. (1979) conducted a numerical taxonomic analysis of 36 morphological characters on 44 ecotypes from 18 countries, which included the cultivated form commonly known as Portulaca oleracea var. sativa. They found three morphological groups, that form a clime: (1) cool temperate, (2) warm temperate to subtropic and (3) humid subtropic to tropic. They did not propose that these groups should receive nomenclatural recognition.

Danin et al. (1978) proposed nine subspecies, on the basis of seed size, seed surface pattern and chromosome number. However, it may be that these subspecies could be expanded almost ad infinitum on the basis of the variety of seed surface patterns that can be found in the species (Matthews et al., 1993). Legrand (1962) stated that seed size, sepal wings and number of stamens are environmentally influenced and that seed surface pattern was not predictable or dependable as a taxonomic character because of the infinite transition patterns that are present.

In a chemotaxonomic study comparing proteins and free amino acids, Prabhakar and Ramayya (1988) found that, within the complex P. oleracea, the var. ophemera is distinct from vars oleracea and sativa.

Matthews et al. (1993) concluded that P. oleracea exists as a polymorphic species and is not readily divisible into subspecies on the basis of seed surface patterns, chromosome number or other morphological traits that are subject to environmental influences.


Top of page P. oleracea is mostly an annual, but it may be perennial in the tropics. Stems are glabrous, fleshy, purplish-red to green, arising from a taproot, often prostrate, forming mats. The leaves (also fleshy) are alternate, subalternate or opposite, obovate to spatulate with an obtuse or truncate-emarginate apex. The leaves may range from 40 mm x 15 mm up to 60 mm x 25 mm in fertile soils. Apical whorls have 2-5 leaves, usually 4. Axillary hairs are missing, inconspicuous or barely visible. Flowers are in a group at the end of the stem. The 2 sepals are fused at the base of the ovary and may form a wing-like carina 3-4 mm long that can cover the fruit. There are (4)5(6) yellow petals ranging from 3 to 10 mm long by 2 to 8 mm wide with 6-15 (3-20) stamens. The style branches are 3-6, the capsule ranges from 4 to 9 mm, opening at or just below the middle. Seeds are black when mature, but may be red or brown when immature. The seeds are 0.6-1 mm long, usually with granulate to flat-stellate surfaces. However, other patterns, with raised stellate and tuberculate surfaces can occur.

Plant Type

Top of page Annual
Seed propagated
Vegetatively propagated


Top of page P. oleracea grows from sea level to 2600 m (Vengris et al., 1972) and is most common in the temperate and subtropical regions, although it extends into the tropics and higher latitudes. Common latitudes are between 45°N and 40°S, with extension to 58°N in North America and 54°N in Europe (Matthews et al., 1993).

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes


AfghanistanPresentKitamura, 1960
BangladeshPresentHolm et al., 1991
CambodiaPresentWaterhouse, 1993
ChinaPresentHolm et al., 1991
-Hong KongPresentYip, 1976
IndiaPresentHolm et al., 1991
-Andhra PradeshPresentPrabhakar et al., 1990
-ChandigarhPresentKhullar and Dutta, 1973
-Madhya PradeshPresentShukla, 1971
-RajasthanPresentBhandari, 1978
-Uttar PradeshPresentSingh, 1973
IndonesiaPresentWaterhouse, 1993
-JavaPresentBacker & van der Brink, 1963
-KalimantanPresentHolm et al., 1991
IranPresentHolm et al., 1991
IraqPresentHolm et al., 1991
IsraelPresentNovoplansky, 1991
JapanPresentPresent based on regional distribution.
-HokkaidoPresentOhwi, 1965
-HonshuPresentOhwi, 1965
-KyushuPresentOhwi, 1965
-ShikokuPresentOhwi, 1965
JordanPresentHolm et al., 1991
Korea, Republic ofPresentKim, 1993
LebanonPresentPost, 1932
MalaysiaPresentWaterhouse, 1993
MyanmarPresentWaterhouse, 1993
NepalPresentHara et al., 1978
PakistanPresentStewart, 1972
PhilippinesPresentMerrill, 1912; Poncho, 1986
Saudi ArabiaPresentChaudhary et al., 1981
SingaporePresentWaterhouse, 1993
Sri LankaPresentGunawardena, 1968
SyriaPresentPost, 1932
TaiwanPresentLi, 1975-79; Li, 1979
ThailandPresentGeesink, 1975
TurkeyPresentWalters, 1964
VietnamPresentJeanplong, 1973


AlgeriaPresentQuezel and Santa, 1962
AngolaPresentHolm et al., 1991
BurundiPresentvon Poellnitz, 1934
CongoPresentvon Poellnitz, 1934
Congo Democratic RepublicPresentHolm et al., 1991
Côte d'IvoirePresentHutchinson and Dalziel, 1954
EgyptPresentTõckholm, 1956
EthiopiaPresentBlundell, 1992
GhanaPresentHutchinson and Dalziel, 1954
GuineaPresentHutchinson and Dalziel, 1954
KenyaPresentBlundell, 1992
LesothoPresentGuillarmod, 1971
LiberiaPresentHutchinson and Dalziel, 1954
LibyaPresentMouterde, 1966
MaliPresentHutchinson and Dalziel, 1954
MauritiusPresentBaker, 1877
MoroccoPresentHolm et al., 1991
MozambiquePresentBlundell, 1992
NigerPresentHooker, 1849
NigeriaPresentHutchinson and Dalziel, 1954
RwandaPresentvon Poellnitz, 1934
SenegalPresentHutchinson and Dalziel, 1954
SeychellesPresentBaker, 1877
Sierra LeonePresentHutchinson and Dalziel, 1954
SomaliaPresentBlundell, 1992
South AfricaPresentHolm et al., 1991
-Canary IslandsPresentSiverio et al., 2011
SudanPresentBroun and Massey, 1929
TanzaniaPresentBlundell, 1992
UgandaPresentBlundell, 1992
ZambiaPresentHolm et al., 1991
ZimbabwePresentHolm et al., 1991

North America

BermudaPresentIntroducedBritton, 1918
CanadaPresentPresent based on regional distribution.
-AlbertaPresentIntroducedMiyanishi and Cavers, 1980
-British ColumbiaPresentIntroducedMiyanishi and Cavers, 1980
-ManitobaPresentIntroducedMiyanashi & Cavers, 1980
-New BrunswickPresentIntroducedMiyanishi and Cavers, 1980
-Northwest TerritoriesPresentIntroducedMiyanishi and Cavers, 1980
-Nova ScotiaPresentIntroducedMiyanishi and Cavers, 1980
-OntarioPresentIntroducedMiyanishi and Cavers, 1980
-Prince Edward IslandPresentIntroducedMiyanishi and Cavers, 1980
-QuebecPresentIntroducedMiyanishi and Cavers, 1980
-SaskatchewanPresentIntroducedMiyanishi and Cavers, 1980
-Yukon TerritoryPresentIntroducedMiyanishi and Cavers, 1980
MexicoPresentIntroducedRzendowski and Rzendowski, 1979
USAPresentPresent based on regional distribution.
-AlabamaPresentIntroducedZimmerman, 1976
-AlaskaPresentIntroducedZimmerman, 1976
-ArizonaPresentIntroducedZimmerman, 1976
-ArkansasPresentIntroducedZimmerman, 1976
-CaliforniaPresentIntroducedZimmerman, 1976
-ColoradoPresentIntroducedZimmerman, 1976
-ConnecticutPresentIntroducedZimmerman, 1976
-DelawarePresentIntroducedZimmerman, 1976
-FloridaPresentIntroducedZimmerman, 1976
-GeorgiaPresentIntroducedZimmerman, 1976
-HawaiiPresentIntroducedZimmerman, 1976
-IdahoPresentIntroducedZimmerman, 1976
-IllinoisPresentIntroducedZimmerman, 1976
-IndianaPresentIntroducedZimmerman, 1976
-IowaPresentIntroducedZimmerman, 1976
-KansasPresentIntroducedZimmerman, 1976
-KentuckyPresentIntroducedZimmerman, 1976
-LouisianaPresentIntroducedZimmerman, 1976
-MainePresentIntroducedZimmerman, 1976
-MarylandPresentIntroducedZimmerman, 1976
-MassachusettsPresentIntroducedZimmerman, 1976
-MichiganPresentIntroducedZimmerman, 1976
-MinnesotaPresentIntroducedZimmerman, 1976
-MississippiPresentIntroducedZimmerman, 1976
-MissouriPresentIntroducedZimmerman, 1976
-MontanaPresentIntroducedZimmerman, 1976
-NebraskaPresentIntroducedZimmerman, 1976
-NevadaPresentIntroducedZimmerman, 1976
-New HampshirePresentIntroducedZimmerman, 1976
-New JerseyPresentIntroducedZimmerman, 1976
-New MexicoPresentIntroducedZimmerman, 1976
-New YorkPresentIntroducedZimmerman, 1976
-North CarolinaPresentIntroducedZimmerman, 1976
-North DakotaPresentIntroducedZimmerman, 1976
-OhioPresentIntroducedZimmerman, 1976
-OklahomaPresentIntroducedZimmerman, 1976
-OregonPresentIntroducedZimmerman, 1976
-PennsylvaniaPresentIntroducedZimmerman, 1976
-Rhode IslandPresentIntroducedZimmerman, 1976
-South CarolinaPresentIntroducedZimmerman, 1976
-South DakotaPresentIntroducedZimmerman, 1976
-TennesseePresentIntroducedZimmerman, 1976
-TexasPresentIntroducedZimmerman, 1976
-UtahPresentIntroducedZimmerman, 1976
-VermontPresentIntroducedZimmerman, 1976
-VirginiaPresentIntroducedZimmerman, 1976
-WashingtonPresentIntroducedZimmerman, 1976
-West VirginiaPresentIntroducedZimmerman, 1976
-WisconsinPresentIntroducedZimmerman, 1976
-WyomingPresentIntroducedZimmerman, 1976

Central America and Caribbean

AnguillaPresentIntroducedHoward, 1988
BahamasPresentIntroducedCorrell, 1982
BarbadosPresentIntroducedGooding et al., 1965
British Virgin IslandsPresentIntroducedHoward, 1988
Costa RicaPresentIntroducedBurger, 1971
CubaPresentIntroduced Invasive Liogier, 1983; Oviedo Prieto et al., 2012
DominicaPresentIntroducedHoward, 1988
Dominican RepublicPresentIntroducedLiogier, 1983
GrenadaPresentIntroducedHoward, 1988
GuadeloupePresentIntroducedFournet, 1978
GuatemalaPresentIntroducedHolm et al., 1991
HaitiPresentIntroducedLiogier, 1983
HondurasPresentIntroducedHolm et al., 1991
JamaicaPresentIntroducedAdams, 1972
Lesser AntillesPresentIntroducedHolm et al., 1991
MartiniquePresentIntroducedFournet, 1978
MontserratPresentIntroducedHoward, 1988
Netherlands AntillesPresentIntroducedStoffers, 1980
NicaraguaPresentIntroducedSeymour, 1980
PanamaPresentIntroducedD'Arcy, 1987
Puerto RicoPresentIntroducedLiogier and Martorell, 1982
Saint LuciaPresentIntroducedHoward, 1988
Saint Vincent and the GrenadinesPresentIntroducedHoward, 1988
Trinidad and TobagoPresentIntroducedWilliams, 1928
Turks and Caicos IslandsPresentIntroducedHoward, 1988
United States Virgin IslandsPresentIntroducedLiogier and Martorell, 1982

South America

ArgentinaPresentIntroducedLegrand, 1952
BoliviaPresentIntroducedLegrand, 1952
BrazilPresentIntroducedLegrand, 1952
-Rio Grande do SulPresentIntroducedGroth, 1980
ChilePresentIntroducedPizarro, 1966
ColombiaPresentIntroducedHolm et al., 1991
EcuadorPresentIntroducedWiggins and Porter, 1971
French GuianaPresentIntroducedLemée, 1955
ParaguayPresentIntroducedHolm et al., 1991
PeruPresentIntroducedSeidenschwarz, 1986
SurinamePresentIntroducedPulle, 1906
UruguayPresentIntroducedLegrand, 1952
VenezuelaPresentIntroducedRincones, 1992


AlbaniaPresentWalters, 1964
AustriaPresentIntroducedWalters, 1964
BelgiumPresentIntroducedWalters, 1964
BulgariaPresentIntroducedKoleshev and Zhelev, 1987
CyprusPresentIntroducedMeikle, 1977
Czech RepublicPresentIntroducedWalters, 1964
EstoniaPresentIntroducedWalters, 1964
FinlandPresentIntroducedUotila, 1977
FrancePresentIntroducedWalters, 1964
-CorsicaPresentIntroducedWalters, 1964
GermanyPresentIntroducedWalters, 1964
GreecePresentIntroducedWalters, 1964
HungaryPresentIntroducedWalters, 1964
ItalyPresentIntroducedWalters, 1964
-SardiniaPresentDanin et al., 2012
LatviaPresentIntroducedWalters, 1964
NetherlandsPresentIntroducedWalters, 1964
NorwayPresentIntroducedLid and Lid, 1994
PolandPresentIntroducedWalters, 1964
PortugalPresentIntroducedWalters, 1964; Vasconcelos, 1989
Russian FederationPresentIntroducedWalters, 1964
-Central RussiaPresentIntroducedKomarov and, 1936
-Russia (Europe)PresentIntroducedKomarov and, 1936
-Russian Far EastPresentIntroducedKomarov and, 1936
SpainPresentIntroducedCarretero, 1989
-Balearic IslandsPresentIntroducedWalters, 1964
SwitzerlandPresentIntroducedWalters, 1964
UKPresentIntroducedWalters, 1964
Yugoslavia (former)PresentIntroducedWalters, 1964


AustraliaPresentPresent based on regional distribution.
-Australian Northern TerritoryPresentIntroducedJessop, 1981
-New South WalesPresentIntroducedJessop, 1981
-QueenslandPresentIntroducedJessop, 1981
-South AustraliaPresentIntroducedJessop, 1981
-TasmaniaPresentIntroducedJessop, 1981
-VictoriaPresentIntroducedJessop, 1981
-Western AustraliaPresentIntroducedJessop, 1981
FijiPresentIntroducedHolm et al., 1991
Micronesia, Federated states ofPresentIntroducedHolm et al., 1991
New ZealandPresentIntroducedHolm et al., 1991

History of Introduction and Spread

Top of page The region of origin is uncertain, possibly an arid climate such as North Africa (Chapman et al., 1974). Although spred to the New World was thought to have been due to post-Columbian humans (Matthews et al., 1993), archaeological evidence (pollen analysis) suggests that P. oleracea arrived in the New World in pre-Columbian times (McAndrews, 1975).


Top of page P. oleracea is common in fields, gardens, vineyards, lawns, driveways, dunes, beaches, salt marshes, waste areas, eroded slopes, bluffs and riverbanks.

Habitat List

Top of page
Terrestrial – ManagedCultivated / agricultural land Present, no further details Harmful (pest or invasive)
Protected agriculture (e.g. glasshouse production) Present, no further details Harmful (pest or invasive)
Managed forests, plantations and orchards Present, no further details Harmful (pest or invasive)
Managed grasslands (grazing systems) Present, no further details Harmful (pest or invasive)
Disturbed areas Present, no further details Harmful (pest or invasive)
Rail / roadsides Present, no further details Harmful (pest or invasive)
Urban / peri-urban areas Present, no further details Harmful (pest or invasive)
Terrestrial ‑ Natural / Semi-naturalNatural forests Present, no further details Harmful (pest or invasive)
Natural grasslands Present, no further details Harmful (pest or invasive)
Riverbanks Present, no further details
Wetlands Present, no further details Harmful (pest or invasive)
Coastal areas Present, no further details Harmful (pest or invasive)

Hosts/Species Affected

Top of page P. oleracea competes for resources with many field crops, particularly herbaceous species that are germinating or growing in competition. Affected crops include: asparagus, red beets, celery, crucifers, cotton, maize, onions, potatoes, rice, soyabeans, sugarcane, tomatoes and wheat.

Host Plants and Other Plants Affected

Top of page

Biology and Ecology

Top of page Genetics

Cytologically, P. oleracea is characterized by a sequence of polyploids, from a base number of x=9. There are diploid races (2n=18) in Africa, Central and North America; tetraploid races (2n=36) in India, Central and North America and hexaploid races (2n=54) in India, Africa, Europe, North America and Hawaii. There are additional reports of 2n=45 in India and 2n=52 in Japan. For further information see Hagerup (1932), Cooper (1935), Sugiura (1936), Steiner (1944), Heiser and Whitaker (1948), Sharma and Bhattacharyya (1956), Mulligan (1961), Walters (1964), Bouharmont (1965), Khullar and Dutta (1973), Danin et al. (1978), Sanjappa (1978), Boquar (1986), Danin and Anderson (1986), Nyananyo and Okoli (1987), Kim and Carr (1990b), Matthews et al. (1993).

Physiology, Phenology and Reproductive Biology

P. oleracea is mostly an annual, but it may be perennial in the tropics. From a typical, open, disturbed habitat purslane grows rapidly, producing flowers, fruits and seeds within 6 weeks of germination. It has a wide tolerance of photoperiod, light intensity, temperature, moisture and soil type. Seeds germinate under conditions that enhance the survival of seedlings. The species is self-compatible.

Purslane reproduces primarily from seed. Over 6000 seeds can be produced after the first flush of flowers (5-6 weeks of growth). One plant can produce between 100,000 and 242,000 seeds over an entire season. A germination rate of over 90% has been recorded after 2.5 years and other germination studies have shown 39% germination after 0.2 years, 78% after 1 year, 59% after 7 years, and 59% after 14 years; 40-year-old seeds were viable. Over 60% of seed remains viable after passage through a house sparrow (Passer domesticus).

Light is required for germination, but the temperature requirement is variable. Seeds can germinate at 10°C in the northern USA and in India, seeds germinate over the range 10-40°C, but not above 50°C. Germination response to light and temperature varies according to the site of origin and the time of seed maturation. In the dry season, seeds that developed on the upper 20% of the plant were less dormant than seeds from the lower 20%. El-Keblawy and Al-Ansari (2000) investigated the effects of site of origin, time of seed maturation and seed age on germination behaviour.

The temperature below which development of P. oleracea ceases was determined by Steinmaus et al. (2000). Kruk and Benech Arnold (1998) modelled thermal responses in Argentina. Results allowed the determination of seed germination models that predict the occurrence of seedling emergence in the field and the dynamics of seed dormancy within those periods. P. oleracea seedlings can represent about 15% of the seed bank each year in the Corn Belt of the USA.

Vegetative reproduction can occur by the development of adventitious roots from the base of cut shoots, but there is no evidence of adventitious rooting from unwounded shoots.

After germination, purslane branches almost immediately. Flowers can be produced in day lengths from 4-24 hours. There is no flowering photoperiod. Capsule production and overall plant growth increase with day length. Capsules can mature under soil conditions of high or low moisture. Flowers will not open on cloudy days or days when the temperature is below 21°C. When opened, they remain open for four hours. The flowers are self-fertile and do not exhibit apomixis. No insect pollinators have been observed during a three-year study. Some investigators have said that the flowers are wind-pollinated, but the pollen is very sticky, a characteristic that is not present in windborne pollen.

Environmental Requirements

C4 metabolism allows P. oleracea to optimize photosynthesis in conditions of high heat and bright sunlight while enduring periods of limited water availability (Koch and Kennedy, 1982). Lara et al. (2003) suggested that there is an induction of a Crassulacean acid-like metabolism (CAM) after 21-23 days of drought stress in P. oleracea.

Rainfall Regime

Top of page Summer

Soil Tolerances

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Soil drainage

  • free

Soil reaction

  • acid
  • neutral

Soil texture

  • heavy
  • light
  • medium

Special soil tolerances

  • shallow

Natural enemies

Top of page
Natural enemyTypeLife stagesSpecificityReferencesBiological control inBiological control on
Baris arctithorax Herbivore Stems
Bipolaris indica Pathogen Leaves
Ceutorhynchus portulacae Herbivore
Dichotomophthora indica Pathogen
Dichotomophthora portulacae Pathogen Leaves/Stems
Drechslera portulacae Pathogen Seedlings
Heliodines quinqueguttata Herbivore
Hypurus bertrandi Herbivore Fruits/pods/Leaves/Seeds/Stems California
Hypurus portulaceae Herbivore
Nysius vinitor Herbivore Seeds
Pegomya rufescens Herbivore
Schizocerella pilicornis Herbivore Leaves California

Notes on Natural Enemies

Top of page The natural enemies of P. oleracea listed refer to recent investigations aimed at finding biological control agents; it is premature at this stage to indicate their importance. For further investigations into the potential for biocontrol of this weed see Zakharyan and Akopyan (1974); Gadoury and Watson (1987); Waterhouse (1993).

The insects include Schizocerella pilicornis, Hypurus bertrandi, Nysius vinitor and Baris arctithorax. Their primary activity involves leaf mining, with some activity on the external parts of leaves, stems and fruits.

For further information, see Norris (1985), Awadallah et al. (1976a, b), Elshafie (1976), Gorske and Hoppen (1976), Gorske et al. (1976), and Clement and Norris (1982).


Fungal infections include Dichotomophthora portulacae, Drechslera indica, Helminthosporium portulacae [Drechslera portulacae] and several strains of Actinomycetes.

For further information, see Norris (no date), Klisiewicz et al. (1983), Strider and Chi (1984), Vegh and LeBerre (1984), Klisiewicz (1985), Baudoia (1986), Mitchell (1986), Evans (1987), Kenfield et al. (1989) and Sugawara et al. (1992).

Plant Trade

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Plant parts liable to carry the pest in trade/transportPest stagesBorne internallyBorne externallyVisibility of pest or symptoms
Growing medium accompanying plants
True seeds (inc. grain) Pest or symptoms not visible to the naked eye but usually visible under light microscope
Plant parts not known to carry the pest in trade/transport
Fruits (inc. pods)
Seedlings/Micropropagated plants
Stems (above ground)/Shoots/Trunks/Branches

Impact Summary

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Animal/plant collections Negative
Animal/plant products Negative
Biodiversity (generally) None
Crop production Negative
Environment (generally) None
Fisheries / aquaculture None
Forestry production Negative
Human health Positive
Livestock production Negative
Native fauna None
Native flora None
Rare/protected species None
Tourism None
Trade/international relations None
Transport/travel None


Top of page P. oleracea is an aggressive weed in most agricultural settings. Seeds on or near the surface of the soil germinate rapidly following ploughing (seeds require light for germination), so there is immediate competition with newly sown crops. This rapid growth is usually horizontal, covering the surface of the soil. Yields can be reduced by 20-40%, depending on the crop. Purslane grows best under warm conditions, so crops in subtropical areas are affected more than those in temperate areas.

A field experiment was conducted in China to determine the relationship between the yield loss of summer maize and infestations of P. oleracea. Weed infestations did not significantly affect grain weight or ear number of the maize. The relationship between yield loss and the density of P. oleracea was S-shaped (Ni HanWen et al., 2000).

Field experiments were conducted in Brazil to determine the effect of different periods of weed competetion on groundnuts. The presence of weeds including P. oleracea resulted in decreased pod and kernel yields and groundnut dry matter (Kasai et al., 1997).

Reservoir for Other Pests

Purslane can also act as a reservoir for other diseases, particularly those caused by nematodes and some viruses.

For further information on nematodes, see Ferraz et al. (1978), Bendixen (1982), Kholod (1983), Zem and Lordello (1983), Khan and Khan (1985), Maqbool et al. (1986), Izquierdo et al. (1987), Tedford and Fortnum (1988), Inserra et al. (1989), Dabaj and Jenser (1990), Zehr et al. (1990), Salawu and Afolabi (1994).

For further information on viruses, see Locatelli et al. (1976), Pochard (1977), Locatelli et al. (1978), Dodds and Taylor (1980), Allen et al. (1983), Nasser and Basky (1988), Dikova (1989), van Os et al. (1993), Stevens et al. (1994).

Threatened Species

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Threatened SpeciesConservation StatusWhere ThreatenedMechanismReferencesNotes
Panicum fauriei (Carter's panicgrass)NatureServe NatureServe; USA ESA listing as endangered species USA ESA listing as endangered speciesHawaiiCompetition (unspecified)US Fish and Wildlife Service, 2011
Scaevola coriacea (dwarf naupaka)NatureServe NatureServe; USA ESA listing as endangered species USA ESA listing as endangered speciesHawaiiCompetition (unspecified)US Fish and Wildlife Service, 2010a
Schiedea verticillataUSA ESA listing as endangered species USA ESA listing as endangered speciesHawaiiCompetition - monopolizing resourcesUS Fish and Wildlife Service, 2009
Sesbania tomentosaNational list(s) National list(s); USA ESA listing as endangered species USA ESA listing as endangered speciesHawaiiCompetition - monopolizing resources; Ecosystem change / habitat alterationUS Fish and Wildlife Service, 2010b

Risk and Impact Factors

Top of page Invasiveness
  • Invasive in its native range
  • Proved invasive outside its native range
  • Highly adaptable to different environments
  • Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
  • Has high reproductive potential
  • Has propagules that can remain viable for more than one year
Impact outcomes
  • Ecosystem change/ habitat alteration
  • Negatively impacts agriculture
Impact mechanisms
  • Competition - monopolizing resources
  • Competition
  • Pest and disease transmission
Likelihood of entry/control
  • Highly likely to be transported internationally accidentally
  • Difficult to identify/detect as a commodity contaminant
  • Difficult/costly to control


Top of page P. oleracea appears to be an excellent candidate for inclusion in saline drainage water reuse systems (Grieve and Suarez, 1997). It is highly tolerant of both chloride- and sulphate-dominated salinities, is a moderate selenium accumulator and a valuable vegetable crop for human consumption (Bianco et al., 1998) and for livestock forage. It is also a source of a gum with emulsification properties that can be used in the food industry (Garti et al., 1999).

P. oleracea is a common weed in Australia and can be used as a demulcent, diuretic, antinflammatory and antibiotic (Cowper, 1996).

Uses List

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Animal feed, fodder, forage

  • Fodder/animal feed

Human food and beverage

  • Vegetable


  • Poisonous to mammals

Medicinal, pharmaceutical

  • Traditional/folklore

Similarities to Other Species/Conditions

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Prevention and Control

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The fleshiness of this weed makes it very resistant to desiccation, and hence often inadequately controlled by hoeing.

Physical control can be by mechanical means (Miyanishi and Cavers, 1981) or by the use of polyethylene film mulches to prevent germination (Inada et al., 1973; Kang et al., 1986; Ricotta and Masiunas, 1991; Zhang et al., 1992).

The natural enemies of P. oleracea listed refer to recent investigations aimed at finding biological control agents; it is premature at this stage to indicate their importance. For further investigations into the potential for biocontrol of this weed see Zakharyan and Akopyan (1974); Gadoury and Watson (1987); Waterhouse (1993); however, the primary method of control appears to be by chemical means.

Chemical Control

Atrazine, bentazone, bromoxynil, chloramben, chlorbufam, chlorpropham, chlorsulfuron, clomazone, clopyralid, dimethametryn, diuron, fluazifop-butyl, fluroxypyr, imazethapyr, linuron, methabenzthiazuron, metolachlor, metribuzin, napropamide, naptalam, oxadiazon, oxyfluorfen, pendimethalin, piperophos, pretilachlor, prodiamine, propanil, sethoxydim, simazine, thiazopyr and trifluralin have been used in attempts to control P. oleracea; this list is derived from hundreds of field trial reports, involving preplanting, pre-emergent and post-emergent treatments (concentrations and combinations of different chemicals are available in the literature).

The application of imazaquin, sulfentrazole and diclosulam pre-emergence; propaquizafop post-emergence followed by oxasulfuron + lactofen; haloxyfop followed by chlorimuron + lactofen gave good control of P. oleracea in soyabean (Laca Buendia et al., 1999).

Flumetsulam + trifluralin were more than 90% efficient in controlling P. oleracea with no apparent phytotoxicity (Jovanovic Radovanov et al., 1999).

Selected references for crops used in tests of herbicides to control P. oleracea:

Asparagus: Granier (1990)
Bananas: de Almeida and Texeira (1974)
Celery: Dusky (1983)
Maize: Kahurananga et al. (1973)
Cotton: Quinones (1987); Ramesh-Babu and Rao (1993)
Crucifers: Marion et al. (1985); Sieczka and Creighton (1985)
Onions: Blanco et al. (1982); Deuber et al. (1983)
Potatoes: Shehata et al. (1990)
Rice: dos Santos and Garcia (1983)
Soyabeans: William and Chiang (1976); Gazziero (1982); Gazziero et al., 1983)
Sugarcane: Kuntohartono and Tarmani (1980); Webb and Feez (1987)
Tomatoes: Rizzotto (1972); Acosta (1981)
Wheat: CIMMYT report on wheat improvement in 1979 (1981).

Herbicide Resistance

Greenhouse experiments were conducted to confirm and quantify linuron resistance in P. oleracea collected from a carrot field in Michigan, USA. A preliminary evaluation was made using a flotation test kit to identify resistance to linuron and atrazine. Subsequent greenhouse experiments indicated that P. oleracea was resistant to certains rates of linuron and atrazine. The resistant P. oleracea was also highly resistant to diuron, cyanazine and prometryn but had a low level of cross resistance bromoxynil. Both resistant and susceptible biotypes of P. oleracea were sensitive to hexazinone and bentazone (Masabni and Zanstra, 1999a, b).

Cross resistance to triazines, ureas and amides has been reported (Heap, 2000).


An infusion of rue (Ruta graveolens) was tested for inhibitory effects on germination and growth of the radicle of P. oleracea. The rue infusion and its isolated allelochemicals (5-methoxysporalen, 8-methoxysporalen and quercetin) delayed the onset of germination and decreased germination. It also damaged the radicle of P. oleracea seedlings (Aliotta et al., 1996). These findings offer some promise in the search for natural herbicides.


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GISD/IASPMR: Invasive Alien Species Pathway Management Resource and DAISIE European Invasive Alien Species Gateway source for updated system data added to species habitat list.
Global register of Introduced and Invasive species (GRIIS) source for updated system data added to species habitat list.

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