Oregano is widely used as a culinary spice, most often as a dried herb. Plant oregano in full sun, water when dry and harvest at 4 or 5 in. (10 to 13 cm) tall. It requires little maintenance and makes an excellent edging plant or ground covering even in dry garden spots. This versatile culinary herb is widely used, most often dried, in Italian dishes, tomato sauce, pizza, fish and salad dressing