Larkspur Consolida ajacis
Larkspur (Consolida ajacis) is an annual flowering plant in the Ranunculaceae family, native to Mediterranean region and southwestern Asia. It grows 60 cm–1.2 m (24 in–3.9 ft) tall and 20–35 cm (8–14 in) wide, wants full sun and moderate water, and is hardy to about -10 °C (14 °F). Space plants about 25 cm (10 in) apart.
Plan Larkspur in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Larkspur at a glance
| Type | Annual flowering plant |
|---|---|
| Family | Ranunculaceae |
| Mature height | 60 cm–1.2 m (24 in–3.9 ft) |
| Mature spread | 20–35 cm (8–14 in) |
| Spacing | 25 cm (10 in) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Moderate; drought tolerance low, waterlogging tolerance none |
| Soil pH | 6–7.5 |
| Cold hardiness | About -10 °C (14 °F) once established (roughly USDA zone 8) |
| Heat stress | Likely above about 27 °C (81 °F) |
| Flowering | about 11–16 weeks after planting, for 4–6 weeks |
| Days to maturity | About 100 days from planting |
| Wind tolerance | Low |
| Pollinator value | High |
| Edible | Not grown as food |
| Native to | Mediterranean region and southwestern Asia |
| Common in gardens of | 🇬🇧 United Kingdom, 🇫🇷 France |
Is Larkspur toxic?
- People: severely toxic
- Cats: severely toxic
- Dogs: severely toxic
- Parts: all parts, seeds, young leaves
Diterpenoid alkaloids (such as ajacine) are neurotoxic and can cause vomiting, weakness and heart and breathing problems; seeds and young plants are most toxic.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Larkspur
No well-documented helpful pairing. Group it with plants that like full sun and moderate water.
Keep apart or take care
- caution With Delphinium: Delphinium and larkspur share the same slugs, snails and mildew problems, and both are poisonous, so keep them away from play areas and grazing pets. Evidence C
Questions about Larkspur
- How far apart should I plant Larkspur?
- About 25 cm (10 in) apart, centre to centre. A mature plant spreads 20–35 cm (8–14 in).
- Does Larkspur need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Larkspur need?
- Moderate water. Drought tolerance is low and waterlogging tolerance none.
- How cold-hardy is Larkspur?
- It tolerates about -10 °C (14 °F) once established, roughly USDA zone 8. As an annual it is usually planted out after the last frost.
- When does Larkspur flower?
- About 11–16 weeks after planting, for 4–6 weeks.
- Is Larkspur poisonous to cats and dogs?
- For cats it is severely toxic; for dogs severely toxic; for people severely toxic. Diterpenoid alkaloids (such as ajacine) are neurotoxic and can cause vomiting, weakness and heart and breathing problems; seeds and young plants are most toxic.
- What grows well with Larkspur?
- There is no well-documented companion pairing for Larkspur. Group it with plants that like the same sun (full sun) and water (moderate).
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- RHS Plant Finder, Royal Horticultural Society
- Missouri Botanical Garden Plant Finder, Missouri Botanical Garden
- ASPCA Toxic and Non-Toxic Plant List, ASPCA
Notes and assumptions
- Typical garden-form values; cultivars and local conditions differ.
- Hardy annual that resents transplanting; best sown in place in autumn or early spring.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Hellebore (Lenten rose) Helleborus x hybridus
- Delphinium Delphinium elatum hybrids
- Common columbine Aquilegia vulgaris
- Japanese anemone Anemone hupehensis
- Love-in-a-mist Nigella damascena
- Globeflower Trollius europaeus
- Christmas rose Helleborus niger
- Persian buttercup Ranunculus asiaticus