Salvia guaranitica 'Black and Blue'
Salvia guaranitica ‘Black and Blue’ is an anise‑scented sage prized for cobalt blue flowers set against nearly black calyces. The contrast is the signature trait. It thrives in full sun with moisture‑retentive but well‑drained soil and warm summers. It is root‑hardy only in warmer parts of North America and is often grown as an annual elsewhere. Plants reach shrub‑like size in long summers and feed hummingbirds from midsummer to frost. Foliage has a noticeable anise scent when bruised.
At‑a‑glance
- Group/Class: Anise‑scented sage
- Height × spread: 3-5 ft × 3-5 ft (0.9-1.5 m × 0.9-1.5 m)
- Bloom window: mid‑summer to frost
- Color & flower form: deep blue tubular flowers with black calyces on long spikes
- Fragrance: 2 noticeable
- USDA hardiness: 8-10; grown as annual in colder zones
- Breeder / Year / Origin: unknown
- Awards/registration: Plant of Merit (MBG)
- Pet safety: safe
How it differs
- Unique black calyces give high contrast compared with typical blue salvias.
- Taller, more open habit than bedding mealycup sages.
- Fragrant foliage unlike many border salvias.
Strengths
- Very attractive to hummingbirds and butterflies.
- Blooms through late season in heat.
- Deer tolerance commonly reported.
Care in one minute
- Site: full sun to light afternoon shade in hot interiors.
- Soil: fertile but well‑drained; avoid water‑logging.
- Water: keep evenly moist the first season; drought tolerant once established.
- Feeding: modest; excess nitrogen can make stems lanky.
- Grooming: remove spent spikes; cut back after first frost where perennial.
- Overwintering: mulch crowns deeply in zones 8-9; take cuttings in late summer in colder areas.
Watch‑outs
- Marginal cold hardiness; protect crowns or lift in zones colder than 8.
- Can sprawl if grown in shade or rich soil.
- Downy or powdery mildew possible in humid conditions.
Best uses (tags)
pollinators; back of border; late season; focal accent; large containers
Provenance note
A selected form of South American S. guaranitica with distinctive dark calyces; widely grown in warm regions and recognized as a Plant of Merit.
References
- Missouri Botanical Garden – Salvia guaranitica ‘Black and Blue’
- RHS – Salvia guaranitica ‘Black and Blue’ profile
- NC State Extension – Salvia (genus overview)
Written by: Your Flowers Guide editorial team
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