scarlet pimpernel

plant

Also known as: Anagallis arvensis, poor-man’s weatherglass

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 23, 2026

Quick Summary

The scarlet pimpernel, scientifically known as Anagallis arvensis, is a low-growing herb native to Europe and naturalized in North America. This plant, belonging to the primrose family, is characterized by its small, solitary flowers that can be red, pink, or blue.12

Often called "poor-man's weatherglass," the scarlet pimpernel has a unique characteristic: its flowers close up in cloudy weather, serving as an informal indicator of changing conditions. The plant typically grows between 6 to 30 cm (2.4 to 12 inches) tall. The name "Scarlet Pimpernel" is also famously associated with a fictional hero who rescued others from danger.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

pimpernel
The scarlet pimpernel (A. arvensis), also called poor-man’s weatherglass, is an annual native to Europe but is naturalized elsewhere, including North America. It grows 6 to 30 cm (2.4 to 12 inches) tall and has red or blue flowers.
Read More
The scarlet pimpernel (A. arvensis), also called poor-man’s weatherglass, is an annual native to Europe but is naturalized elsewhere, including North America. It grows 6 to 30 cm (2.4 to 12 inches) tall and has red or blue flowers.
Read More