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Styracaceae family

American Snowbell Styrax americanus

Native

American Snowbell is a perennial tree native to the lower 48 states. It grows to 10 ft and blooms Apr in full sun – part shade.

Growing & care

USDA PLANTS · TRY
Conditions
Sources · Conditions
USDA PLANTS — Sun
USDA — SoilPH — Soil pH
USDA PLANTS (DwCA, Zenodo 17903503) — Fertility Requirement / Soil Adaptation — Adapts to
USDA — Temp-Min °F — Hardiness
Niinemets & Valladares 2006 (CC0) — Drought tolerance · Shade tolerance · Wet-soil tolerance
Sun
Full sun – part shade
Soil pH
4.5–8.5
Adapts to
Coarse (sandy), Medium (loam)
Hardiness
USDA zone 6+
Drought tolerance
Moderate
Shade tolerance
Moderate
Wet-soil tolerance
Low waterlogging
Size & form
Sources · Size & form
USDA PLANTS (DwCA, Zenodo 17903503) — Height, Mature — Height
USDA PLANTS (DwCA, Zenodo 17903503) — Planting Density (per acre) — Spacing
USDA PLANTS — Lifespan
TRY Plant Trait Database (CC BY 4.0) · USDA PLANTS — Foliage
McKenzie et al. 2025 — community-science image analysis (MIT) — Flower colour
Height
10 ft
Spacing
4–6 ft apart from USDA planting density
Lifespan
Perennial
Foliage
Deciduous broadleaf · fine texture
Flower colour
White AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
In the garden
Sources · In the garden
USDA PLANTS (DwCA, Zenodo 17903503) — Propagation Method / Commercial Availability — Propagate by
USDA PLANTS (DwCA, Zenodo 17903503) — Germination (cold stratification) — Seed starting
USDA PLANTS — Seed Period — Seeds ripen
USDA PLANTS (DwCA, Zenodo 17903503) — Foliage Texture / Browse Palatability / Resprout — Resprouts if cut
Propagate by
Cuttings
Seed starting
Needs cold stratification a cold-moist spell before it germinates
Seeds ripen
Summer – Autumn seed-collection / harvest window
Resprouts if cut
No
Shrub layer — Sits in the shrub of a layered food forest or polyculture.Open guide →
Rain garden / bioswale — Rated OBL on the wetland list — tolerates wet feet, so it suits the soggy zone of a rain garden or bioswale that catches and filters runoff.Open guide →
derived roles
AI = read by an AI vision model · DERIVED = a computed estimate, not a direct measurement. The “How we know this” section below details each.
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 · Apr — USDA PLANTS (DwCA, Zenodo 17903503) — BloomPeriod
When to sow · for your area

Sow timing keys off your local last- and first-frost dates.

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 ~1 caterpillar species

Styrax supports ~1 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 modest genus.

Recorded feeding on Styrax in North America, including:

Callosamia promethea · Promethea Moth ✦ Papilio glaucus · swallowtail butterfly ✦
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). ✦ = recorded on this exact species.
✦ Bees 5 bee visitors
Visitor records (observations, not exhaustive) from Noori et al. 2026 (CC BY 4.0) · GloBI →
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.
Frequently grows with

Across 63 U.S. vegetation-survey plots that recorded American Snowbell, these catalog species turned up most often in the same plot — a real field co-occurrence signal, not a planting prescription.

Red Maple · 67% Eastern Poison Ivy · 65% Blackgum · 63% Swamp Titi · 57% Sweetgum · 56% Bald Cypress · 49% Smallspike False Nettle · 46% Muscadine · 43%
"%" = share of this plant's plots that also held the species. From sPlotOpen → (Sabatini et al. 2021, CC BY 4.0) — open vegetation plots: wild community composition, not garden design.
How we know this (2) 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).
Flower colour Derived

McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.

Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.

McKenzie, P., Berardi, A.E., Hopkins, R. (2025). flower_color_phenology (MIT).
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 (33) 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)
[18] Invasive / introduced status — USDA PLANTS (DwCA, Zenodo 17903503) — native status
[19] Wetland indicator — USACE National Wetland Plant List (2022)
[21] Ecological value — Warren II 2026 (CC0) · Tallamy host-use counts
[22] Conservation rank — NatureServe Explorer (CC BY)
[24] Functional traits — TRY Plant Trait Database (CC BY 4.0)
[25] Climate niche — Derived — realized climate niche from U.S. county occurrences (GBIF) × NOAA NCEI county climate normals 1991–2020 (public domain)
[27] Stress tolerance — Niinemets & Valladares 2006 (CC0)
[29] Flower-visitor value (derived) — Noori et al. 2026 (CC BY 4.0) · GloBI
[30] Caterpillar host count — Warren II 2026 (Dryad, CC0) · Tallamy host-use counts
[31] Caterpillar species — NHM HOSTS (CC0)
[32] 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).

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