Rhodiola L.

Stonecrop (en), Rhodiole (fr)

Genus

Angiosperms > Saxifragales > Crassulaceae

Characteristics

Herbs perennial, with some dimorphism. Rhizome a fleshy caudex, thick or slender, apex usually at or slightly above ground level. Caudex leaves present, usually reduced and scalelike, but sometimes with well-developed leaf blade. Flowering stems 1 to many, arising from axils of caudex leaves, annual, simple, leafy; dried remains of old stems sometimes persisting. Stem leaves usually alternate, occasionally verticillate or opposite, simple, fleshy. Inflorescences terminal, a simply or compoundly corymbiform or dichotomous cyme, less often 1-flowered, rarely a helicoid cyme or with additional axillary inflorescences arising from distal leaf axils, usually bracteate and pedunculate. Flowers usually bisexual, sometimes unisexual (when plants dioecious, or gynodioecious in Rhodiola alsia subsp. alsia and rarely in R. purpureoviridis subsp. phariensis). Calyx (3 or)4-or 5(or 6)-parted. Petals ± free, as many as sepals. Stamens in 2 series, usually 2 × as many as petals; antepetalous stamens adnate to basal part of petals; anthers mostly purple before anthesis, later turning yellow, basifixed or less often dorsifixed, 2-loculed. Nectar scales linear, oblong, suborbicular, or quadrangular. Ovary superior; carpels as many as petals. Follicles few to many seeded.
More
Herbs, perennial (dying back in winter to rootstock), not viviparous, 0.3-6 dm, glabrous [pubescent]. Stems a rootstock with apex mostly above ground, erect, spreading, or decumbent, commonly branching to form clumps, fleshy, with brown scalelike [or green] leaves; flowering stems from axils of brown scale-leaves on stout rootstock partly above ground. Leaves persistent, cauline, alternate, sessile, subclasping basally; blade elliptic to ovate or oblanceolate to linear, obovate, or oblong, laminar (mostly to 1 mm thick), 0.5-5.5 cm, somewhat fleshy, base not spurred, margins entire or toothed; veins not conspicuous. Inflorescences cymose or spikelike to subcapitate. Flowers bisexual or unisexual, erect, 4-6-merous; sepals connate basally, all alike (unequal in R. rosea); petals erect or spreading, distinct, greenish, white, rose, dark red, or yellowish; calyx and corolla not circumscissile in fruit; nectaries quadrate to linear; stamens 2 times as many as sepals, epipetalous; filaments mostly adnate to corolla at base; pistils erect, nearly distinct; ovary base straight; styles 2+ times shorter than ovary. Fruits erect. Seeds oblanceoloid or pyriform, ribbed, finely cross-ribbed.
Life form perennial
Growth form herb
Growth support -
Foliage retention deciduous
Sexuality hermaphrodite
Pollination -
Spread -
Mature width (meter) -
Mature height (meter) 0.03 - 0.6
Root system rhizome
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Flower color
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Nitrogen fixer -
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Environment

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Hardiness (USDA) 4-9

Usage

Uses -
Edible -
Therapeutic use -
Human toxicity -
Animal toxicity -

Cultivation

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