Annual. Use Sorrel sparingly as an herb and salad green. Sorrel is a flavorful ingredient known for its sour, acidic taste reminiscent of lemon zest. An early spring salad green and herb, popular in England. This strong lemon flavor adds a bit of pep when it is still cold out. Tender greens grow 6 to 8″ and in zones 4-9 will come back every year. Packet contains about 2 grams of seed.