Field ManualAll plants

Empress tree
Paulownia tomentosa (Thunb.) Steud.
Pet & Human Safety
People: No hazard foundPets: Not on the ASPCA lists as we read them
No pet-toxicity listing for this species was found in our sources (ASPCA checked). 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.
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- Hardiness zones
Oregon State: hardy to USDA zone 5. Trees and Shrubs Online: USDA 6, RHS hardiness H6, AGM
- Light
Sun to part shade (Oregon State).
- Water needs
Always finger-test two inches down.
- Mature size
US: Oregon State: 30-60 ft (9-18 m) tall; UK: Trees and Shrubs Online: to about 25 m; in northern Europe the common form is seldom much over 15 m
How to prepare the soil, when and what to feed, and how and when to prune where that applies.
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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.
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Vintage Plates
Old botanical drawings from public libraries are in the app, for plants where we have them.
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