Lobelia × speciosa 'Starship Blue'
‘Starship Blue’ is a compact, upright selection in the Starship F1 fan‑hybrid series. Plants reach about 24 to 28 inches tall with deep violet‑blue flower spikes. Bloom begins in midsummer and can continue into fall with deadheading. It prefers sun to part shade with steady soil moisture. It is more heat tolerant than many older hybrids and performs in humid regions. Cold hardiness is lower than the species, so treat as short‑lived in colder zones.
At‑a‑glance
- Group/Class: × speciosa fan‑hybrid; F1 series; herbaceous perennial
- Height × spread: 24-28 in (61-71 cm) × 8-12 in (20-30 cm)
- Bloom window: mid summer to early fall
- Color & flower form: Deep violet‑blue tubular flowers on columnar spikes
- Fragrance: 0 none
- USDA hardiness: zones 6-10
- Breeder / Year / Origin: PanAmerican Seed; year unknown; USA
- Pet safety: avoid
How it differs
- Shorter and more columnar than a typical Great Blue Lobelia clump.
- Blooms earlier and may rebloom with deadheading.
- Shows better heat tolerance than many older fan hybrids.
- Less cold hardy than the species; winter survival drops north of zone 6.
Strengths
- Uniform habit and earlier flowering commonly reported by the breeder.
- Good vertical accent for small spaces and containers.
- Performs in humid, warm summers with steady moisture.
Care in one minute
- Site and light: full sun to part shade; afternoon shade in hot areas.
- Soil and pH: fertile, evenly moist, well‑drained soil; avoid standing water.
- Watering: keep consistently moist through bloom.
- Feeding: mix in compost; light balanced fertilizer in spring for container plants.
- Grooming: deadhead to encourage continued bloom; remove spent spikes.
- Overwintering: mulch lightly in zone 6; replant where winters are colder.
Watch‑outs
- Short‑lived in cold climates; treat as an annual or replant every few years.
- Requires consistent moisture; avoid letting containers dry out.
- May suffer crown rot in saturated, poorly drained soils.
Best uses (tags)
borders, containers, rain gardens, pollinators, seasonal impact
Provenance note
The Starship series derives from crosses among Lobelia cardinalis and Lobelia siphilitica; ‘Starship Blue’ is listed as selection ‘PAS1302712’.
References
- PanAmerican Seed – Lobelia Starship Blue
- Royal Horticultural Society – Lobelia × speciosa ‘Starship Blue’
- Chicago Botanic Garden – Lobelia × speciosa Starship Deep Rose (series hardiness reference)
- NC State Extension – Lobelia (toxicity and culture)
Written by: Your Flowers Guide editorial team
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