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Home / Browse / Geranium / Carolina Geranium (var. sphaerospermum)
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Pictured: Geranium carolinianum — the species. This variety isn’t separately illustrated.
Geraniaceae family

Carolina Geranium (var. sphaerospermum) Geranium carolinianum var. sphaerospermum variety

Native Specialist-bee host

Carolina Geranium (var. sphaerospermum) is an annual wildflower native to Canada and the lower 48 states. A host for pollen-specialist native bees.

More about this plant

Geranium carolinianum is a species of geranium known by the common name Carolina crane's-bill, or Carolina geranium. It is an annual herb native to North America, where it is widespread and grows in many types of habitat. There are two varieties; G. carolinianum var. carolinianum and G. carolinianum var. sphaerospermum. It may be considered an invasive species outside the southeastern United States. Wikipedia →

Growing & care

USDA PLANTS · TRY
Conditions
Sources · Conditions
Cold hardiness (derived) — Hardiness
Hardiness
≥ zone 4 derived from its U.S. range
Size & form
Sources · Size & form
USDA PLANTS — Lifespan
Lifespan
Annual
In the garden
Herb layer — Sits in the herb of a layered food forest or polyculture.Open guide →
derived roles
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 ~24 caterpillar species

Geranium supports ~24 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.

Recorded feeding on Geranium in North America, including:

Amblyptilia pica · Geranium Plume Moth Amphipyra tragopoginis · Mouse Moth Anavitrinella pampinaria · Common Gray Apamea devastator · Glassy Cutworm Arachnis picta · Painted Tiger Moth Archips purpurana · leafroller moth
+ 8 more species →
Argyrotaenia citrana · leafroller moth Argyrotaenia velutinana · Red-Banded Leafroller Carmenta giliae · clearwing moth Choristoneura rosaceana · Oblique-Banded Leafroller Epinotia ruidosana · leafroller moth Euproctis chrysorrhoea · tussock moth Helicoverpa zea · Corn Earworm Heliothis oregonica · Oregon Gem
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 specialist-bee host

Specialist native bees depend on it.

Some native bees are pollen specialists (oligolectic) — they raise young only on pollen from particular plant genera. Geranium is a recorded specialist-bee host, so losing it can mean losing the bee that relies on it.

Xerces pollinator conservation →
Specialist hosts from Smith et al. 2024.
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.
Sources for this entry (12) 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
[06] Description — Wikipedia (CC BY-SA)
[07] Ecological value — Warren II 2026 (CC0) · Tallamy host-use counts · Smith et al. 2024 (CC BY)
[08] Cold hardiness (derived) — Derived from U.S. range × USDA PHZM zones
[10] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[11] Caterpillar species — NHM HOSTS (CC0)
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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).

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