Lamb's ear (Stachys byzantina) and mullein (Verbascum sp.) are plants with velvety, wooly leaves. Besides looking alike, they are in different families, require slightly different conditions, and have other growth habits. Lamb's ear grows in zones 4a through 9a and can be used as a winter or spring annual in zones 9b through 11, although it cannot survive hot, humid summers. Mullein grows in USDA zones 3 through 9 and is an invasive weed in all states except the northernmost U.S.