A period cheese recipe from MS Harley 5401:
To make Chese Nesh at is Ouer Hard. Lay þe chese lappyd all about in fayr grene nettyls. And lat it ly styll on a fayre borde or on a floore, and within fow[r] dayes it schall be nesgh & fresh.
To make Soft Cheese that is “Too Daring.” Lay the cheese in a fair green nettle wrap. And let it lay still on a fair board on the floor, and within four days it shall be soft and fresh.
The nettle (cynara cardunaculus) is the rennet that is needed in order to create curds in cheese.
This was found over here.