As with all lilies, the tiger lily produces bulbs underground. As the plant matures, the bulbs grow larger, taking on the task of providing nutrition back to the plant. The bulb is both the means of reproducing and sought after as a food for people. Native tribes used it extensively for their meals. Be vigilant with cats around tiger lilies, since these plants are toxic to cats.
Growing tiger lilies from bulb scales is easy according to Wallace Hansen of Northwest Native Plant Nursery & Gardens. The lilies' flowers die off by the end of July; by early August, you can harvest the bulbs from healthy plants by breaking off a few leaf scales from the lower part of the main bulb. Place the main bulb back into the ground where it will produce more plants. The scales are placed in a perlite filled plastic bag with a little water and stored in the dark with a room temperature of 60-to-70 degrees Fahrenheit. When the roots begin to develop shallowly, re-pot the bulbs in peat moss and perlite and watch them grow.
Different Indian tribes have harvested the tiger lily bulbs at different times of the season. According to the Royal British Columbia Museum, some tribes preferred a spring harvest while others dug the bulbs up in late fall. The bitter-tasting bulb was used both as a seasoning like garlic and a side dish. After boiling or steaming it would be mashed and then dried for later use. In some states the tiger lily is a protected species. Know the state laws before you dig up a wild one.
Lily bulbs are still consumed today by many families and are available in Asian and health food stores or in mainstream groceries with an extensive vegetable department.. A typical recipe for a lily bulb salad from the PBS television program, "The Victory Garden," includes lily bulbs and stems, onion, wild onions, asparagus and olive oil. The ingredients are mixed with a black bean vinaigrette and served chilled. Many Asian stir-fry recipes call for thinly sliced lily bulbs.