Urtica pilulifera aka Roman Nettle
Taxonomy ID: 12815
Urtica pilulifera, or Roman nettle, belongs to Urticaceae, the nettle family. Its native range spans the Mediterranean, western Pakistan and the Arabian Peninsula. Kew classes it as part of the subtropical flora. It is not native to Britain or Ireland. This annual grows to about 2 feet [0.6 metres]. It grows on farmed ground and waste sites, and favours light soils.
Hairs on the leaves sting when you touch them. They can irritate skin, so wear thick gloves when you gather leaves. Flowers bloom from June to September. Each plant bears male flowers and separate female flowers. Wind moves pollen between flowers, but the species is not self-fertile. Seeds ripen from July to October. The seed season thus lasts into autumn. The plant ends its life cycle within one year.
Roman nettle needs an open site with no shade. It prefers moist soil and grows in sand, loam or clay. It accepts soils that are slightly acid, neutral or slightly alkaline. It suits ground with high levels of nitrogen. Deep, rich soil gives the best fibre crop. Plants For A Future says it is not frost tender. Growers can sow its seed in a cold frame in spring. The source lists garden beds as a place to grow it.
Young leaves serve as cooked greens or go into soups and stews. They supply vitamins and minerals and can stand in for spinach. Cooking the leaves or drying them fully removes the sting. Use only young leaves for food. Older leaves form gritty cystoliths, which can irritate the kidneys. Young shoots also have a use in brewing nettle beer. People have used the plant as a herb, including leaf tea taken as a tonic. These past uses do not prove that it has health benefits.
The stems yield strong fibre for cord, cloth and paper. Growers gather the fibre as growth dies back in early autumn. Leaves and stems yield green dye, while roots yield yellow dye. Oil from the seeds has served as fuel for lamps. People have also steeped the leaves to make a hair rinse. Its recorded uses thus reach beyond food to fibre, colour and oil.
Common names
Roman Nettle, Pill Bearing NettleMore information about Roman Nettle
How difficult is it to grow Urtica pilulifera?
Urtica pilulifera (Roman Nettle) is very easy to grow, as it is essentially a weed species that thrives in disturbed soils with minimal care. The main requirements are full sun exposure and consistently moist soil. It tolerates a wide range of soil types from sandy to clay and adapts to various pH levels. The primary challenge is managing its stinging hairs during handling—always wear thick gloves when working with this plant.
How do I propagate Urtica pilulifera?
Urtica pilulifera propagates primarily through seeds. Sow seeds in spring in a cold frame or directly outdoors after the last frost. The seeds require no special treatment and germinate readily in moist soil. The plant can also spread vegetatively through underground rhizomes, which allows it to establish and survive in suitable habitats. Once established, it may self-seed if flower heads are left to mature.
How big does Urtica pilulifera grow?
Urtica pilulifera is a fast-growing annual that typically reaches 30-60cm (1-2 feet) in height, though it can grow up to 1 meter under optimal conditions with rich, moist soil. The plant has a stout, erect stem that may branch, with quadrangular (square-shaped) cross-section. It completes its entire lifecycle from germination to seed production within one growing season, flowering from June to September.
Does Urtica pilulifera flower?
Yes, Urtica pilulifera produces inconspicuous greenish-white to yellow-green flowers from June to September. The flowers appear in elongated clusters called axillary racemes. The plant is monoecious, meaning individual flowers are either male or female, but both sexes occur on the same plant. Seeds ripen from July to October after successful wind pollination. The flowers are small and not ornamentally significant.
How is Urtica pilulifera pollinated?
Urtica pilulifera is wind-pollinated and monoecious, meaning each plant bears both male and female flowers. However, the plant is not self-fertile, requiring cross-pollination between different individuals for successful seed production. The small, inconspicuous flowers are adapted for wind pollination rather than attracting insect pollinators. Seeds ripen approximately one to three months after flowering begins.
Can Urtica pilulifera be grown outdoors?
Urtica pilulifera is strictly an outdoor plant that cannot be grown indoors as it requires full sun and will not tolerate shade. It thrives in USDA hardiness zones 4-9 and is not frost tender. The plant naturally grows in disturbed soils including cultivated land, waste places, roadsides, and meadows. It prefers nitrogen-rich soil and develops the best fiber on deep, fertile soils. Native to the Mediterranean region, it has naturalized in parts of Northern Europe and North America.
What pests and diseases affect Urtica pilulifera?
Urtica pilulifera is generally resistant to pests and diseases due to its stinging hairs, which deter most herbivores. The plant actually serves as an important host for certain butterfly and moth caterpillars, which have evolved to feed on nettle species. Its robust, weedy nature means it rarely suffers from significant pest or disease problems. No major pest or disease issues are documented for this species in cultivation.
Is Urtica pilulifera edible?
Yes, Urtica pilulifera is edible with an edibility rating of 3 out of 5. Young leaves can be cooked as a potherb or spinach substitute and are highly nutritious, rich in vitamins and minerals. The shoots can be used to make nettle beer, and the plant yields edible oil. Always wear thick gloves when harvesting, and only use young leaves as older leaves contain cystoliths that may irritate the kidneys. Cooking or drying completely neutralizes the stinging hairs.
What are the medicinal uses of Urtica pilulifera?
Urtica pilulifera has a medicinal rating of 3 out of 5 with a long history of traditional use. The whole plant functions as an antiasthmatic, depurative, diuretic, galactogogue, haemostatic, and tonic. Traditionally used to treat anemia, excessive menstruation, hemorrhoids, arthritis, rheumatism, and skin conditions like eczema. Modern research has confirmed anti-inflammatory, antioxidant, and antihyperglycemic properties. Best harvested in May-June when flowering, then dried for later use.
What are other uses of Urtica pilulifera?
Urtica pilulifera has an other uses rating of 3 out of 5, primarily valued for fiber production. The stems yield a strong, flax-like fiber historically used for rope, cloth, paper, and string since the Bronze Age. The plant produces dyes: green from leaves and stems, yellow from roots. An infusion of leaves makes an effective antidandruff hair treatment. As a companion plant, it reportedly increases essential oil production in neighboring herbs.
What temperature does Urtica pilulifera need?
Urtica pilulifera thrives in temperate climates and tolerates a wide temperature range, growing in USDA zones 4-9. The plant is not frost tender, meaning it can withstand light frosts. Native to the Mediterranean and subtropical regions, it adapts well to both warmer and cooler temperate climates. As an annual, it completes its lifecycle during the warm growing season from spring through fall.
How does care for Urtica pilulifera change seasonally?
As an annual plant, Urtica pilulifera completes its entire lifecycle in one growing season. Sow seeds in spring after frost danger passes. During summer, maintain moist soil conditions and ensure full sun exposure. The plant flowers from June to September and sets seed from July to October. No overwintering care is needed as the plant dies after setting seed. Collect seeds in autumn if you wish to replant the following year.
What is the region of origin of Roman Nettle
What are the water needs for Roman Nettle
What is the right soil for Roman Nettle
What is the sunlight requirement for Roman Nettle
How to fertilize Roman Nettle
Is Roman Nettle toxic to humans/pets?
Sources
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