wall pepper

noun

a small Eurasian crassulaceous plant, Sedum acre, having creeping stems, yellow flowers, and acrid-tasting leaves

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Examples from the Web for wall pepper

Historical Examples of wall pepper

They have a hot sharp taste, and the plant is sometimes called "Wall-Pepper."
Wildflowers of the Farm
Arthur Owens Cooke