Plot & PetalField ManualAll plants
Hemsley snowball
Styrax hemsleyanus Diels
Pet & Human Safety
People: No hazard foundPets: Not on the ASPCA lists as we read them
ASPCA has no page for this plant. Do not treat as pet-safe.
PlotAndPetal cannot tell you whether a plant you found can be eaten. Only someone who can see the plant can identify it.
Poison control
If someone has collapsed, cannot be woken, is having a seizure or has trouble breathing, call 911 now. For any other possible poisoning, call Poison Help: 1-800-222-1222.
Emergency number source: U.S. federal law (47 U.S.C. § 251(e)(3)), read 2026-10-07.
Naturalist Lore
Historical Background & Breeding Lore
The history of this plant and its name, and how it was bred, where we have them.
Get the app: coming soonCare
- Hardiness zones
USDA 5a-9b; RHS hardiness rating H5 (Trees and Shrubs Online); described as hardy down to -15 C (5 F) but needs shelter from drying winds
- Water needs
moderate moderate is a plain-language reading of "good, moist soil" (Trees and Shrubs Online); no watering figure on the page. Always finger-test two inches down.
- Mature size
Trees and Shrubs Online: tree to 12 m (39 ft) tall in the wild description; Sidbury Manor 13 m, Bodnant about 12 m, JC Raulston Arboretum 8 m in 2009
How to prepare the soil, when and what to feed, and how and when to prune where that applies.
Get the app: coming soonAnatomy & Guilds
Botanical Anatomy & Characteristics
How the flowers and leaves are built and which pollinators visit, where we have them.
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Field Doctor
What can go wrong with this plant and what to do about it, where we have them.
Get the app: coming soonVintage Plates
Vintage Plates
Old botanical drawings from public libraries are in the app, for plants where we have them.
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