Papaver somniferum
Opium poppy
(c) David Perez, some rights reserved (CC BY) · licence
Family: Papaveraceae · Type: Herb · Not Native
Papaver somniferum (Opium poppy) is a non-native California herb in the Papaveraceae family, recognized by large size, glaucous appearance, and massive round capsules.
Opium poppy is a naturalized perennial found in the California Floristic Province in disturbed areas and fallow fields at elevations below 500 meters. Flowering from June to August, this plant produces white to red or purple flowers with four to six centimeter petals, often featuring dark spots at the base of the petals. Growing 60 to 120 centimeters tall with a glaucous appearance and sparse or absent hairs, the plant has an upright, robust form with distinctive stem-clasping leaves. Its cauline leaves are 10 to 20 centimeters long, spreading broadly along the stem with bases that wrap around and grip the main stem. The plant produces large, round fruits measuring 3 to 5 centimeters in diameter, creating distinctive seed capsules after flowering.
Identification and appearance
Key characters: 5 sympatric species; key features are large size, glaucous appearance, and massive round capsules
Habitat and range
Habitat: Disturbed areas, fallow fields
Elevation: < 500 m
Outside California: United States, native to Eurasia
Bloom period
Papaver somniferum blooms Jun-Aug.
How to tell it apart
vs Eschscholzia: Papaver capsule opens by top pores; Eschscholzia splits lengthwise and sits in cup-shaped base.; vs Oreomecon: Papaver fruit is broader than long; Oreomecon fruit is longer than broad.; vs Rosa: Papaver has 4-6 separate petals; Rosa has 5 petals and thorny stems.; vs Ranunculus: Papaver has 2 sepals that drop early; Ranunculus has 5 persistent sepals.; vs Tropaeolum: Papaver has capsule fruit; Tropaeolum has wrinkled nutlet fruits in threes.
Frequently asked questions
Is Papaver somniferum native to California?
No. Papaver somniferum is not native to California (recorded as not native).
When does Papaver somniferum bloom?
Papaver somniferum blooms Jun-Aug.
What plant family does Papaver somniferum belong to?
Papaver somniferum is in the Papaveraceae family, genus Papaver.
What habitat does Papaver somniferum grow in?
Papaver somniferum grows in Disturbed areas, fallow fields.
Related species
Other California species in the same genus, family, or bioregion.
- Papaver sp.
- Papaver argemone — Long pricklyhead poppy
- Papaver californicum — Fire poppy
- Papaver heterophyllum — Wind poppy
- Papaver hybridum — Rough poppy
- Papaver rhoeas — Corn poppy
- Papaveraceae sp. — Poppy family
- Platystemon californicus — Cream cups
- Platystemon californicus var. ciliatus — Santa Barbara Island cream cups
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.