Ocimum basilicum. Dark Opal basil is a stunning, ornamental herb known for its deep purple, almost black leaves and fragrant aroma. This variety not only adds a splash of color to gardens but also provides a unique flavor, combining traditional basil sweetness with a hint of spice. Ideal for both culinary and decorative use, Dark Opal basil can be used in salads, pesto, and as a garnish.