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Rue, Common

Herbaceous Perennial Flower, Herb

Also known as Herb of Grace, Herb of Repentance
Ruta graveolens
Rutaceae Family

Valued primarily for its unusual compund, blue-green foliage that retains color well into winter. The 3-foot-tall plants are used as accents or clipped into a low hedge in formal gardens. Caution: Plants are toxic and can cause irritation with skin contact.

	Site and Plant Characteristics
	Growing Information
	Varieties

Site Characteristics

Sunlight:

full sun
part shade

Prefers full sun but tolerates part shade.

Soil conditions:

tolerates droughty soil
requires well-drained soil
tolerates low fertility

Thrives in hot, dry sites.

Hardiness zones:

4 to 9

Might only be marginally hardy in Zone 4.

Special locations:

xeriscapes

Plant Traits

Lifecycle: perennial

Evergreen subshrub. Usually dies back to the ground.

Ease-of-care: easy

Height: 1.5 to 3 feet

Spread: 1 to 2.5 feet

Bloom time:

mid-summer
late summer

Flower color: yellow

Dull yellow flowers borne in lax terminal clusters.

Foliage color: blue-green

Foliage texture: fine

Foliage is fine and dense.

Shape:

upright
round
columnar

Rounded columnar form makes an excellent accent plant.

Shape in flower: same as above

Special Considerations

Special characteristics:

deer resistant
non-aggressive - May self-seed.
non-invasive
not native to North America - Native to the Balkan Peninsula and the Crimea but widely naturalized in Europe and North America.
evergreen - Semi-evergreen with foliage lasting well into winter.
fragrant - The foliage has a sharp, bitter acrid scent that many find disagreable.
bears ornamental fruit - Seedheads used in dried arrangements.

Attracts:

beneficial insects - Provides a breeding area for tiny parasitic wasps that control whiteflies.

Special uses:

dried flowers - Seedheads are particularly attractive in dried arrangements.

Growing Information

How to plant:

Propagate by seed, cuttings, layering, division or separation - Can be grown from seed, but varieties must be propagated vegetatively, except for 'Variegata', which breeds true from seed.
Plants freely self sow. But if planting the seeds, start them in pots in a cold frame, and grow until well-established before planting out.
Take stem cuttings of half-ripe wood in July or August and hold in a cold frame until well rooted.
Take root cuttings of young plants in spring.
Layering in early summer is easy. Old plants will often self-layer.

Maintenance and care:

Caution: Rue is poisonous and can cause skin irritation. Wear gloves and long sleeves.
Prune stems back to 6 to 8 inches in early spring to shape plant and encourage new growth.
Deadhead or remove flowers when they are just developing to prevent foliage from yellowing and fading. Do not prune in late summer or plants may not harden off in time for winter.
Seldom needs division. May need mulching for winter protection.
More growing information: How to Grow Perennials

Varieties

'Blue Beauty' has bright blue green leaves.
'Blue Mound' is a compact form with deep blue green foliage.
'Jackman's Blue' is the strongest blue variant with an almost disagreeable scent.
'Variegata' has leaves with white variegation. Breeds true from seed.