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.'" (DE)
English reference (DE): Vol. 1, Book 1, Hadith 628 (DE)
Arabic reference (DE): Book 1, Hadith 671 (DE)