Scientific: Eustoma
russellianum (Synonyms: Eustoma gracile, Eustoma grandiflorum, Lisianthius glaucifolius, Lisianthus grandiflorum, Lisianthius russellianus)
Common: Texas bluebell, lisianthus, prairie gentian
Family:
Pronounciation: Ewe-STO-ma rus-sel-li-AN-um
Hardiness zones
Sunset All
USDA All
Landscape Use: Mixed spring, summer, and fall flower borders, accent, containers.
Form & Character: Erect, stiff, formal, fragile, delicate, colorful, cheerful.
Growth Habit: Evergreen, herbaceous, semi-succulent annual, moderate growth rate depending on hybrid selection ranging from 4-inches to 2-feet tall, usually narrow with few lateral branches.
Foliage/Texture: Glaucous, ovate to oblong simple leaves that are sessile and clasp about glaucous stems; medium texture.
Flowers & Fruits: Terminal large blossoms to as much as 3-inches across, single and double, many colors ranging from white to deep violet/purple with dark colored centers; fruit inconspicuous.
Seasonal Color: Blooms throughout the summer.
Temperature: Intolernat of cold. Prefers warm weather, but is stressed during the highest heat of a Phoenix summer.
Light: Full sun to partial shade, but avoid hot western exposures.
Soil: Well-drained and organic-amended soils are best, salt sensitive.
Watering: Regular garden water.
Pruning: None is needed, except to remove spent flower heads to keep plants visually tidy.
Propagation: Set out as transplants in Phoenix in April and May for summer bedding plant color. Otherwise, propagated by seed, especially improved F1 hybrid selections such as the 'Echo' Series and the 'Heidi' series.
Disease and pests: Root rot in warm poorly-drained soils, lisianthus necrosis virus.
Additional comments: Texas bluebell is one of three species of Eustoma. It has received much attention by horticultural breeders to produce several improved F1 hydrids for landscape garden use as colorful bedding plants. The large flowers of the improved F1 hybrids can be as much as 3-inches wide. What limits its usefulness in Phoenix as a bedding plant is (like you and me) its sensitivity to the extreme Phoenix summer heat.
