It was narrated that Umm Qais bint Mihsan said:
"I asked the Messenger of Allah about menstrual blood that gets on clothing. He said, 'Wash it with water and lote leaves, and rub it, even with a piece of stick.'" (IT)
English reference (IT): Vol. 1, Book 1, Hadith 628 (IT)
Arabic reference (IT): Book 1, Hadith 671 (IT)