Scarlet Larkspur is a tall perennial native to southwestern California that blooms in late spring/early summer with cardinal red and yellow flowers. It grows 3-6 feet tall and 1-2 feet wide, with finely lobed green foliage and toxic parts. It requires full sun, well-drained soil, and no summer watering after blooming. Scarlet Larkspur is an excellent choice for water-wise gardens, providing colorful blooms and habitat for hummingbirds and butterflies.

1. Scarlet Larkspur – Delphinium cardinale
(del-FIN-ee-um kar-dih-NAL(or NAYL)-ee)
Family: Ranunculaceae (Ranunculus or Buttercup Family)
Native to: Southwestern CA from Monterey to San Diego Co. & Baja (locally in Santa Monica Mtns);
hot, dry openings and slopes (often talus) in chaparral below 5000 ft.
herbaceous perennial
mature height: 3-6 ft.
mature width: 1-2 ft.
Tall herbaceous perennial from a woody root. Foliage dies back prior to flowering and entire plant
dies to the ground in summer drought. Leaves medium green, finely lobed (typical of Delphiniums).
Like all Delphiniums, all plant parts are quite toxic when eaten, particularly the roots.
Growth characteristics:
Blooms in late spring/early summer – usually May-June. Cardinal red & yellow
flowers on tall flowering stalks. Flowers are 2 inches long, pea-like with characteristic ‘spur’. This is
an extremely showy plant in bloom. When massed they are unusually lovely & exotic.
Blooms/fruits:
Uses in the garden: Makes a wonderful tall summer perennial for the backs of water-wise flower
beds. Does well on dry hillsides and other difficult to water places. Good choice in part-shade under
oaks or other summer-dry trees/shrubs. Flower stalks make lovely cut flowers. Likes heat.
Sensible substitute for: Non-native Delphiniums.
Attracts: Excellent hummingbird & butterfly habitat; hummingbird pollinated.
Requirements:
Element
Sun
Soil
Water
Fertilizer
Other
Requirement
Full sun (along immediate coast) to part shade (morning sun or dappled sun best).
Well-drained; rocky is great. Any local pH.
Needs summer dormant period; no summer water after blooming (Zone 1).
None needed, but light fertilizer OK.
Fine with organic mulches.
Management:
Hollow stems – plants likely will need to be staked. Cut back dead stalks.
Propagation: from seed: need moist/cold treatment
by cuttings: ??
Plant/seed sources (see list for source numbers): 10, 11, 13, 16, 19, 20, 31
5/2/11
* Native to CA but not to Western L.A. Co.
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