Wild lisianthus produces flowers in shades of white and purple.

Is Lisianthus Poisonous?

by Teo Spengler

Lovely lisianthus is an American wildflower that graces the prairies of the Southwest with its delicate, rose-like blossoms. Lisianthus (Eustoma grandiflorum), also called Texas bluebell and prairie gentian, thrives as a biennial in U.S. Department of Agriculture plant hardiness zones 8 through 10. It can prove tricky to grow but contains no known toxins, so you can feel safe inviting lisianthus into your garden.


It is fun to have lisianthus in your garden because nothing is subtle about this plant. In summer, the plant sends up 3-foot stalks, each of which produces six to eight flowers from the upper leaf axils. Each blossom has five waxy petals that flare out slightly and curl at the tip so that the flower looks like large bell. With myriad cultivars on the market, you can select your lisianthus plant's height, flower color and blossom size.


Lisianthus is picky about just about everything. It wants to sink its roots into neutral or alkaline soil and shows its displeasure with acidic soils by growing poorly. The plant demands full-sun and moist, very well-drained soil. Humid or rainy climates do not agree with lisianthus plant, nor does transplanting, given its deep taproot. You have to stake the stalks to keep the heavy-headed flowers from tipping over, and deadhead as you go. Don't plant lisianthus seeds unless you are prepared to wait five months from the time you plant to the date your first bloom appears.


The delicate beauty of these flowers needs front row planting. You can use them in beds and borders as long as they are near the front so they won't be hidden by bigger, stronger flowers. If you buy dwarf cultivars that only get 6 to 8 inches tall, you can use them in patio pots or indoors as houseplants. The long stalks of lisianthus make them fun cutting flowers and easy to arrange in vases; the big blossoms last over three weeks in water.


Although lisianthus flowers and foliage do not contain poisonous toxins, it is never good for kids or pets to eat ornamental garden plants. Teach your children while they are young that they should not snack on plant parts without asking an adult. Young children should not be allowed to wander about the backyard unsupervised. On the other hand, getting youngsters interested in a vegetable garden gives them experience in growing plants that they can eat.

About the Author

From Alaska to California, from France's Basque Country to Mexico's Pacific Coast, Teo Spengler has dug the soil, planted seeds and helped trees, flowers and veggies thrive. World traveler, professional writer and consummate gardener, Spengler earned a BA from U.C. Santa Cruz, a law degree from Berkeley's Boalt Hall, and an MA and MFA from San Francisco State. She currently divides her life between San Francisco and southwestern France.

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