opium poppy
Refers specifically to the opium poppy (Papaver somniferum), the plant from which opium is derived.
Cultivation of opium poppies is prohibited by law.
The opium poppy flower is beautiful, but opium can be obtained from its seed pod.
In that country, the cultivation of opium poppies is banned by law.
When early summer comes, poppy flowers bloom across the whole field.
ポピー is the general English-derived word covering all poppy species, while 芥子 specifically denotes the opium poppy (Papaver somniferum).
Written identically as 芥子, けし means the opium poppy plant while からし (also written 芥子) means mustard, the condiment made from a different plant's seeds.
Katakana spelling is common for this plant name; usually written in kana.
Hiragana spelling, also common.
Kanji form, but rarely used; the source has no high priority for this form.
Rarely used kanji form.
The word ケシ is of native Japanese origin, but its exact derivation is uncertain. The kanji forms 芥子 and 罌粟 are Chinese borrowings used for this plant.