What Is Star Anise?

A spice native to eastern Asia, the dried fruit of star anise (Illicium verum) resembles a woody, brown, eight-pointed star, each ray a 1/2-inch "canoe" that holds a single seed. It’s important that you not mistake this fruit for the fruits of similar members of its plant family, such as Japanese anise (Illicium anisatum), because most of those others are highly poisonous. Plants for a Future warns that star anise fruit also can be toxic in large amounts. So use it sparingly. Both trees are hardy in U.S. Department of Agriculture plant hardiness zones 8 through 11.

The star anise tree can grow to 50 feet in height and has leathery, green leaves 4 to 6 inches long and red or pink-tinged white flowers or green-tinged yellow ones in summer. The 1-inch fruits mature about one year after the flowers appear but are usually picked and dried while still immature, after they turn yellow-brown in mid-autumn.

You probably won’t have any luck trying to start seeds from supermarket star anise because those fruits will have been dried. The World Agroforestry Organization warns that the seeds should be planted while their moisture content remains above 30 percent. A friend or seed seller who owns a star anise tree may be able to keep some harvested seeds damp and refrigerated for you.

Immediately after you receive the seeds, place them in a refrigerator – inside a zipper-type plastic bag with a handful of damp seed-starting mix. Leave the bag of seeds in the refrigerator for two months.

Then sow the seeds 1 inch apart and about 1/3 inch deep in a soil combination that is 1 part seed-starting mix and 1 part sand, ensuring you use a container with bottom drainage holes. After topping the container with plastic wrap, place it on a warm shelf where the temperature remains between 72 and 77 degrees Fahrenheit. A Danida Forest Seed Centre leaflet reports that the seeds should germinate within four to eight weeks.

While the seedlings are young, keep them under a grow light or on a partially shaded windowsill. Gradually expose them to more sunlight as they near the 1-year mark, after which they can be transplanted into the ground. Star anise trees prefer full or partial sun and humus-rich, well-drained, acidic soil with a pH between 4.0 and 6.0. Space the trees 15 feet from each other and from other plants . According to James A. Duke's CRC Handbook of Alternative Cash Crops, star anise trees should begin fruiting when they are 6 to 10 years old.