Rue

Ruta graveolens

Easy · Beginner friendly

About Rue

Ruta graveolens, rue or herb of grace, is a small Mediterranean evergreen subshrub with blue-green, deeply lobed aromatic leaves and clusters of yellow summer flowers. Once common in monastery gardens, apothecary plots, and old kitchens, rue now earns its place mostly as a foliage plant and historical herb. The scent is strong, bitter, and resinous, and the plant's chemistry demands respect: sap can cause severe photosensitive skin reactions, especially in bright sun. Handle with gloves and keep it away from casual grazing. In dry gardens it is handsome, drought-tolerant, and useful as a host plant for swallowtail butterflies. Its beauty is cool and blue; its temperament is not casual.

Fragrant
Drought-tolerant
Evergreen
Pollinator-friendly

WATER

Regular

Top inch dry

LIGHT

Full sun

6+ hrs direct

HARDY

Hardy to -20°F (-29°C)

USDA hardiness zones 5–9

How to care for Rue

Watering

Springevery 14 days
Summerevery 21 days
Fallevery 21 days
Winterevery 45 days

Soil · Well-draining

Top dressingPine bark mulch10%
Main mixPotting soil + perlite 2:170%
DrainageLECA / gravel20%

Never skip the drainage layer — standing water is the top cause of root rot.

FERTILIZER

This plant needs little to no feeding.

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At a Glance

NativeEurope, North America
Height2–3 ft (0.6–0.9 m)
Spread1.5–2.5 ft (0.5–0.8 m)
Flower colorYellow
Foliage colorBlue-green
SoilLoamy, Well-drained, Alkaline
LocationsYard

Bloom time

BLOOM CYCLE

Peak bloom

Jun–Aug

Small yellow flowers in summer

Fragrance

STRONG FRAGRANCE

Sharp pungent aroma—acrid to many people.

Toxicity

Humans Toxic · Pets Moderate

furanocoumarins (psoralens), rutin, and quinoline alkaloids

HumansDogsCats

Toxic

Leaf
Sap
Contact
Ingestion

EXPOSURE Touching leaves and sap. Eating leaves and sap.

EFFECT Severe phytophotodermatitis, blistering, hepatotoxicity (ingested), and abortifacient.

NOTE Documented concern for humans: Severe phytophotodermatitis, blistering, hepatotoxicity (ingested), and abortifacient.

Moderate

Leaf
Sap
Contact
Ingestion

EXPOSURE Touching leaves and sap. Eating leaves and sap.

EFFECT Phytophotodermatitis and vomiting.

NOTE Extremely photosensitizing—wear gloves and handle only in low light. ASPCA lists rue as toxic.

Moderate

Leaf
Sap
Contact
Ingestion

EXPOSURE Touching leaves and sap. Eating leaves and sap.

EFFECT Phytophotodermatitis and vomiting.

NOTE Extremely photosensitizing—wear gloves and handle only in low light. ASPCA lists rue as toxic.

Educational information, not medical or veterinary advice. If exposure is suspected, contact a doctor or veterinarian.

DISTRIBUTION

Native
Introduced

Europe
North America

History

Ruta graveolens, commonly called common rue or herb-of-grace, is an evergreen aromatic subshrub in the citrus family (Rutaceae) native to the Balkans, southeastern Europe, and parts of southwestern Asia. Carl Linnaeus described it in Species Plantarum in 1753. The epithet graveolens means strong-smelling.

The plant has a millennia-long history in European and Middle Eastern medicine and herbalism—mentioned in the Bible (Luke 11:42), used by Ancient Greek and Roman physicians, valued in medieval monastic herb gardens, listed in the 8th-century Capitulare de Villis of Charlemagne, and prescribed against plague in the 'Four Thieves Vinegar'. Plants grow 60-90 cm tall with distinctive pinnately divided glaucous blue-green leaves and terminal clusters of small yellow four-petaled flowers with green central discs in summer. Contains furanocoumarins (psoralens) that cause severe phytophotodermatitis—skin contact with the sap plus sunlight produces painful burns and long-lasting dark pigmentation.

Also carries significant internal toxicity and was historically used as an abortifacient. Important larval host for giant swallowtail butterflies in North America. Native to the Balkan Peninsula. Used since antiquity in Mediterranean medicine and cuisine. Mentioned by Pliny, Hippocrates, and in the Bible.

Symbolism & meaning

What It Symbolizes

Rue can symbolize repentance, Shakespeare's 'herb of grace' offered for sorrow and remembrance in scenes of grief and madness. Another layer is protection, for it was a medieval guardian against witchcraft and evil, hung in doorways and tucked into ritual bouquets. Few herbs so completely braid Christian penitence with older folk magic, and to grow ruta graveolens is to keep a small piece of that double inheritance, equally at home in a sermon and in a charm.

Repentance — Shakespearean 'herb of grace' for sorrow and remembrance
Protection — medieval guardian against witchcraft and evil

Where the Name Comes From

'Ruta' from Greek 'rhyte', the ancient name; 'graveolens' means strong-smelling.

Uses & Fun Facts

Historical herb-of-grace used in folk medicine
Blue-green foliage releases pungent bitter scent
Yellow flowers host swallowtail butterfly caterpillars
Traditional protective herb in Mediterranean folklore

Related plants

Plants with similar care

Frequently asked questions

How often should I water Rue?

In summer, water about every 21 days; in winter, about every 45 days. Adjust for heat, pot size and drainage.

How much light does Rue need?

Full sun: 6+ hrs direct. Watch the leaves — scorching or stretching means the light needs adjusting.

Is Rue toxic to cats or dogs?

Pets Moderate (Dogs Moderate · Cats Moderate) Educational information, not medical or veterinary advice. If exposure is suspected, contact a doctor or veterinarian.

Is Rue easy to grow?

Yes — it is considered an easy, beginner-friendly plant.

When does Rue bloom?

It typically blooms Jun–Aug in the Northern Hemisphere.

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