Sp. Pl. 1: 445. 1753.


Gen. Pl. ed. 5, 204. 1754.

Common names: Purslane
Etymology: Latin portula, little door, in reference to the lid of the capsule
Treatment appears in FNA Volume 4. Treatment on page 496. Mentioned on page 457, 458.

Herbs, annual (perennial in P. suffrutescens). Roots tuberous, fleshy, fibrous, or small taproots. Stems erect to prostrate, branched, fleshy or suffrutescent; trichomes in inflorescence or stem nodes absent or present, glabrous otherwise. Leaves alternate or subopposite, congested and involucrelike immediately proximal to inflorescence; blade terete, subterete, or flattened. Inflorescences terminal in clusters, or axillary on short branches. Flowers sessile or subsessile, usually open only in sunshine; sepals broadly clasping at base, herbaceous to scarious, falling from top of capsule; petals ephemeral, 5–7, usually distinct, margins usually entire; stamens (4–)6–40(–100); ovary half inferior to inferior, plurilocular proximally to 1-locular distally, placentation free-central; style 1, short, stigmas 3–8(–18). Capsules membranaceous, chartaceous, dehiscence circumscissile. Seeds many, brown to black or gray, reniform to cochleate; seed coat smooth or variously sculptured, granular to stellate-tuberculate or spiny. x = 4, 5, 8, 9.


Nearly worldwide, primarily tropical and subtropical, also temperate.


Species 100–125 (10 in the flora).


Key Based on Flowering Material

1 Petals pink to purple > 2
1 Petals yellow, orange, copper, bronze, or white > 6
2 Flowers 25 mm or more diam.; petals 15 mm or longer Portulaca grandiflora
2 Flowers to 25 mm diam.; petals 12 mm or shorter > 3
3 Leaf blades flattened, 2-12 mm wide, obovate to spatulate or oblanceolate Portulaca amilis
3 Leaf blades terete to hemispheric, 0.5-3 mm wide, linear to lanceolate > 4
4 Petals deeply 2-lobed; stamens 40 or more; stem nodes with inconspicuous trichomes; restricted to sandstone outcrops in s Georgia Portulaca biloba
4 Petals not 2-lobed; stamens usually fewer than 30; stem nodes with conspicuous trichomes; widespread in United States > 5
5 Petals medium pink to almost white; seeds 0.6 mm or more diam., elongate; restricted to granitic outcrops in Georgia, North Carolina, South Carolina, Virginia Portulaca smallii
5 Petals dark pink to purple; seeds 0.6 mm or less diam., orbiculate; wide- spread throughout se, lower Midwest, and sw United States Portulaca pilosa
6 Flowers 25 mm or more diam > 7
6 Flowers 20 mm or less diam > 8
7 Plants perennial; roots tuberous; stems stiffly erect; sw United States Portulaca suffrutescens
7 Plants annual; roots fibrous; stems prostrate to suberect; widespread Portulaca grandiflora
8 Leaf blades terete to hemispheric, linear to lanceolate, usually 3 mm or less wide > 9
8 Leaf blades flattened, obovate or spatulate (sometimes lanceolate in P. umbraticola), 2-15 mm or more wide > 10
9 Stem nodes and inflorescences with conspicuous trichomes; flowers less than 8 mm diam.; Midwest and sw United States Portulaca halimoides
9 Stem nodes and inflorescences with inconspicuous trichomes; flowers more than 9 mm diam.; tropical Florida Portulaca rubricaulis
10 Capsules encircled by expanded, membranaceous wing Portulaca umbraticola
10 Capsules not winged Portulaca oleracea

Key Based on Fruiting Material

1 Capsules each encircled by expanded, membranaceous wing Portulaca umbraticola
1 Capsules not winged > 2
2 Leaf blades flattened > 3
2 Leaf blades terete to hemispheric > 4
3 Trichomes at stem nodes absent or inconspicuous; seeds 0.6-1.1 mm or more diam. Portulaca oleracea
3 Trichomes at stem nodes conspicuous; seeds 0.4- 0.6 mm or less diam Portulaca amilis
4 Stem nodes with inconspicuous trichomes > 5
4 Stem nodes with conspicuous trichomes > 6
5 Seeds 0.7 mm or more diam., surface cells distinctly stellate, tuberculate Portulaca biloba
5 Seeds less than 0.7 mm diam., surface cells obscurely stellate, without tubercles Portulaca rubricaulis
6 Seeds 0.6-1 mm diam > 7
6 Seeds 0.3-0.65 mm diam > 8
7 Longest leaves usually longer than 20 mm; capsules usually more than 4 mm diam Portulaca grandiflora
7 Longest leaves usually shorter than 15 mm; capsules 3.5 mm or less diam. Portulaca smallii
8 Capsules 2 mm or less diam.; lateral seed coat with densely arranged, flattened, stellate cells, tubercles absent; seeds averaging 0.5 mm or less diam. Portulaca halimoides
8 Capsules 1.5-5 mm diam.; seed coat with loosely arranged, stellate cells; tubercles usually present; seeds averaging more than 0.5 mm diam > 9
9 Plants annual; roots fibrous to slightly fleshy; stems prostrate or suberect to erect Portulaca pilosa
9 Plants perennial; roots tuberous; stems stiffly erect Portulaca suffrutescens
... more about "Portulaca"
James F. Matthews +
Linnaeus +
Purslane +
Nearly worldwide +, primarily tropical and subtropical +  and also temperate. +
Latin portula, little door, in reference to the lid of the capsule +
Sp. Pl. +  and Gen. Pl. ed. +
1753 +  and 1754 +
legrand1962a +, matthews1985a +, walters1964a +  and wilson1932b +
Portulaca +
Portulacaceae +