Indigo Spires salvia

Sun

Full sun; light afternoon shade is useful in very hot climates.

Water

Water regularly while establishing, then deeply when the soil begins to dry. Established plants tolerate short dry spells, but prolonged drought reduces flowering.

Soil

Well-drained soil of average fertility; avoid ground that stays wet in winter.

Height

3-5 ft (0.9-1.5 m)

Spread

3-4 ft (0.9-1.2 m)

Flowers

Violet-blue flowers on long spikes from early summer until autumn frost; flowering may continue longer in frost-free climates.

Foliage

Aromatic, mid-green, oval to lance-shaped leaves with toothed edges. Usually dies back with frost but may retain foliage in frost-free gardens.

Growth

Fast

Care needed

Medium

• Pollinators
• Deer resistant
• Heat tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   2.5 ft (0.76 m)

3. After 2 years

   4 ft (1.2 m)

   full size

About 2 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Fast

• Plant after frost danger has passed, leaving room for its broad, arching growth.
• Water at soil level when the upper soil dries; do not keep the roots constantly wet.
• Apply compost in spring; avoid heavy nitrogen feeding, which encourages floppy growth.
• Set discreet supports around the clump early in the growing season if the site is exposed.
• Mulch the root area before winter where it is hardy, keeping mulch clear of the crown.
• In colder regions, take cuttings before frost and keep rooted plants in a bright, frost-free place.

Pruning. Pinch young shoots in spring to encourage branching, and shorten spent flower stems to a leafy shoot to promote more bloom. Where it overwinters outdoors, leave the old stems through winter and cut them back to healthy basal growth in spring.

Early spring

Check overwintered plants and cut away dead stems once new growth appears.

Spring

Plant out after the last frost, add compost and install supports if needed.

Late spring

Pinch soft shoot tips for a bushier plant.

Summer

Water during dry spells and remove spent flower spikes.

Late summer

Take non-flowering shoot cuttings for replacement plants and indoor overwintering.

Late autumn

Mulch outdoor clumps in mild regions; move rooted cuttings under frost-free cover before freezing weather.

• Place toward the middle or back of a sunny mixed border, allowing its flower spikes to arch between neighbouring plants.
• Combine with ornamental grasses for a loose planting with movement and a long flowering season.
• Pair with yellow rudbeckias or orange dahlias for strong colour contrast.
• Use in a large patio container where its spreading stems have space and can be supported.
• Repeat through a pollinator border to provide flowers late in the growing season.

Garden styles it suits: Cottage garden, English country, Pollinator garden, New perennial (prairie), Mediterranean and Blues and silvers.

Plant it with: Coneflower, Black-eyed Susan, Dahlia, Gaura, Switchgrass and Yarrow.

Wildlife: Flowers attract bees, butterflies and, in the Americas, hummingbirds. Deer often leave the aromatic foliage alone, but browsing is still possible.

• Flopping stems: provide full sun, avoid rich nitrogen feeding, pinch young growth and support the clump early.
• Winter root or crown rot: improve drainage and avoid planting in low spots that remain wet.
• Spider mites during hot, dry weather: check leaf undersides, rinse foliage and use insecticidal soap if an infestation persists.
• Slugs and snails on fresh growth: inspect emerging shoots and use barriers, hand-picking or labelled iron-phosphate bait.

Not known to be toxic to people, cats, dogs or horses, although information specific to this hybrid is limited. It is an ornamental salvia, not a substitute for culinary sage; eating plant material may cause stomach upset.

• Mystic Spires Blue salvia (Salvia 'Balsalmisp')

  A compact relative with shorter, denser growth and less sprawling stems; Indigo Spires is substantially taller and looser.

• Mealycup sage (Salvia farinacea)

  Usually smaller and more upright, with shorter flower spikes; Indigo Spires has longer, arching spikes and a broader habit.

• Mexican bush sage (Salvia leucantha)

  Has narrow, grey-green leaves and conspicuously velvety purple flower spikes, often with white flowers; Indigo Spires has greener, broader leaves and less woolly spikes.

Salvia comes from the Latin salvare, meaning 'to heal', while 'Indigo Spires' describes the colour and shape of its flower spikes.

Propagation. Take softwood or semi-ripe cuttings from non-flowering shoots in spring or summer. This hybrid is generally sterile, so propagate vegetatively to retain the cultivar.

Accepted botanical name

Salvia

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.