PlantKey Open ecological atlas
Planner
Home / Browse / Delphinium / Slim Larkspur
iNaturalist — CC, credited & licensed per image
Ranunculaceae family

Slim Larkspur Delphinium depauperatum

Native

Slim Larkspur is a perennial wildflower native to Canada and the lower 48 states. It blooms May – Aug.

More about this plant

Delphinium depauperatum is a species of larkspur known by the common names slim larkspur and dwarf larkspur. This wildflower is native to western North America where it is found in mountain meadows. It grows from a short root and erects a stem usually under 40 centimeters in maximum height. The small leaves are divided into lobes and are usually located about the base of the plant. Toward the top of the stem are flowers on long pedicels, with usually not more than 20 flowers per plant. The flowers generally have deep dark blue sepals which are flat and extended to the sides, and petals which are mainly the same color except for the top two, which may be lighter blue to white. The spur is between one and two centimeters long. Wikipedia →

Growing & care

USDA PLANTS · TRY
Conditions
Sources · Conditions
Cold hardiness (derived) — Hardiness
Hardiness
≥ zone 6 derived from its U.S. range
Size & form
Sources · Size & form
USDA PLANTS — Lifespan
Lifespan
Perennial
In the garden
Herb layer — Sits in the herb of a layered food forest or polyculture.Open guide →
derived roles
The garden year bloom → fruit → fall colour
J
F
M
A
M
J
J
A
S
O
N
D
Bloom
Bloom (the flower's colour)
Bloom · May – Aug — 208 obs · Herbarium specimens — Park et al. 2023 (CC BY 4.0)
Species characteristics from USDA PLANTS (public domain) + TRY (CC BY) — general guidance, not a guarantee for your exact site. Deer "browsing" is documented palatability, not a deer-proof claim.

Wildlife & pollinators

How pollinator value is scored →
❧ Caterpillar hosts ~10 caterpillar species

Delphinium supports ~10 caterpillar species.

Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a moderate genus.

Keystone count (genus-level) from Warren II 2026 (CC0) · Tallamy host-use records. Named species (a documented Nearctic sample, not exhaustive) from NHM HOSTS (CC0).
✦ Bees 1 bee visitor

1 native & managed bee species is documented visiting Slim Larkspur :

Visitor records (observations, not exhaustive) from Noori et al. 2026 (CC BY 4.0) · GloBI →
Wildlife & visitors 1 nectaring

Open records of who else uses Slim Larkspur — a generalist food-web signal, kept separate from the keystone Ecological Value.

1 adult butterfly & moth species is recorded nectaring at its flowers:

Interaction records (observations, not exhaustive) from GloBI → (CC0). Counts are distinct species; names are the most-recorded. Common names from Wikidata (CC0).
Species thumbnails re-hosted from iNaturalist — Creative Commons, credited per image (hover for credit). Click any species to see it on iNaturalist. Not exhaustive; many taxa have no openly-licensed photo yet.
How we know this (1) Methods & honest limits
Climate niche (heat tolerance & native rainfall) Derived

We take the plant’s U.S. county range and look up each county’s long-term climate, then summarise: native rainfall = the median annual rainfall across its counties; heat tolerance = the warm end (90th percentile) of average temperature across its range (mirroring how our cold-hardiness floor uses an extreme). Counties + medians blunt the roadside/observer bias that makes point-level climate unreliable. Needs at least five placeable counties.

Honest limits: A realized, sampling-biased niche (where it has been recorded, not its physiological optimum), and county climate is coarse — large Western counties span deserts and mountains. Derived guide, never a measured fact.

Realized-niche / climate-envelope approach (Pearson & Dawson 2003; Soberón 2007). Climate: NOAA NCEI nClimDiv county normals (1991–2020).
Derived values are computed from open data by a published method — labelled, cited, and never shown as a direct observation. Full methodology →
Sources for this entry (18) Open & cited
[01] Scientific name & family — USDA PLANTS (DwCA, Zenodo 17903503)
[02] Growth habit & duration — USDA PLANTS (DwCA, Zenodo 17903503)
[03] Native status & distribution — USDA PLANTS (DwCA, Zenodo 17903503)
[04] Common name — USDA PLANTS (via GBIF)
[05] Invasive / introduced status — USDA PLANTS (DwCA, Zenodo 17903503) — native status
[07] Description — Wikipedia (CC BY-SA)
[08] Ecological value — Warren II 2026 (CC0) · Tallamy host-use counts
[10] Conservation rank — NatureServe Explorer (CC BY)
[11] Climate niche — Derived — realized climate niche from U.S. county occurrences (GBIF) × NOAA NCEI county climate normals 1991–2020 (public domain)
[12] Cold hardiness (derived) — Derived from U.S. range × USDA PHZM zones
[13] Wildlife & visitors — GloBI — Global Biotic Interactions (CC0)
[15] Flower-visitor value (derived) — Noori et al. 2026 (CC BY 4.0) · GloBI
[16] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[17] Caterpillar species — NHM HOSTS (CC0)
[18] County range — GBIF Open Data — open-licensed occurrences (CC0/CC-BY) → county
Spot an error or have a better photo? Every field links to its source, and the whole dataset is open.
Cite this page Open data, please attribute

PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).

Citation

Loading…

BibTeX
Loading…