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Salvia azurea

giant blue sage

Lamiaceae

Central and southeastern United States

Attracts Pollinators Attracts Butterflies Attracts Hummingbirds Deer Resistant Drought Tolerant Fragrant (light)

Native to North America

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 5–9

Overview

Salvia azurea is an herbaceous perennial in the mint family (Lamiaceae), forming upright to lax stems 3-6 feet (0.9-1.8 m) tall from a woody crown. The square stems carry opposite, narrow, lance-shaped leaves 1-4 inches (2.5-10 cm) long with smooth or slightly toothed margins. From late summer into fall it bears slender spikes of two-lipped flowers, each 0.5-1 inch (1.5-2.5 cm) long, in clear sky-blue and occasionally pale blue or white. The flowers open from the bottom of the spike upward over several weeks and draw bees, butterflies, and hummingbirds. The foliage is aromatic when crushed. It grows naturally in prairies, glades, and dry open ground in full sun. The tall stems often flop without support or a midsummer cutback. One limitation is this lax habit; plants may need staking or pinching to stay upright, and they are short-lived on heavy, wet soils.

Native Range

Salvia azurea is native to the central and southeastern United States, from Nebraska and Minnesota south to Texas and east to the Carolinas and Florida. It grows in prairies, rocky glades, and open woods on dry soils.

Suggested Uses

Salvia azurea is used in prairie and meadow plantings, pollinator gardens, and the back of sunny borders for late-season blue. It combines with grasses and fall-blooming perennials. Its height and lax stems suit informal plantings more than tidy, formal beds.

How to Identify

Square stems 3-6 feet (0.9-1.8 m) tall carry narrow, opposite leaves 1-4 inches (2.5-10 cm) long that smell aromatic when crushed. Slender late-season spikes hold sky-blue, two-lipped flowers 0.5-1 inch (1.5-2.5 cm) long. The clear blue flowers and tall, narrow-leaved habit separate it from Salvia farinacea, which is shorter with mealy-white flower stalks.

Appearance

Size & Dimensions

Height3' - 6'

Width/Spread1'6" - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~6 weeks

Summer Fall

Flowering occurs from late summer into fall, generally August to October. The flowers open in sequence up each spike over four to six weeks. Bloom continues until the first hard frost in mild autumns.

Detailed Descriptions

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.5(Neutral)

357912

Soil Types

sand loam rocky clay

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

Reaches mature size in 2-3 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Salvia azurea grows in full sun on dry to medium, well-drained soil and tolerates poor, sandy, or rocky ground. It withstands heat and drought once established and declines on rich, moist, or poorly drained soil. Cutting the stems back by half in early summer produces shorter, sturdier plants with more branches. Lean soil keeps growth compact, while fertilizer encourages floppy stems. It carries few pests and resists deer browsing. Plants are hardy in USDA zones 5 to 9.

Pruning

Cutting the stems back by one-third to one-half in late spring or early summer reduces flopping and delays bloom slightly. Spent flower spikes can be sheared after bloom. Stems are cut to the ground in late winter before new growth begins.