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Threadleaf Blue Star Amsonia hubrichtii

Phonetic Spelling
am-SO-nee-uh hew-BRIK-tee-eye
Description

Blue star is an uncommon herbaceous perennial in the dogbane (Apocynaceae) family. It is native to the Ouachita Mountains in central Arkansas and Oklahoma, where it was discovered in the early 1940s by Leslie Hubricht. A slow grower, it may take 1 to 2 years before this plant's true beauty can be seen. It forms erect clumps with feathery green foliage, making it an excellent backdrop for low-growing annuals and perennials. 

In the spring it produces clusters of blue star-like flowers followed by slender, elongated seed pods. It is prized for its great fine texture and bright yellow fall color.

Blue star is easily grown in average, medium, well-drained soil in full sun to part shade. It will tolerate poor soils and some drought. The plant will become floppy if grown in too much shade or too rich soils. Use in borders, rock gardens, open woodlands, and in mass plantings.

Named perennial of the year in 2011 by the Perennial Plant Association.

Insects, Diseases and Other Plant Problems:  No serious insect or disease problems. Plants can flop over with too much shade, so cut back after flowering.  Caution should be used when cutting back, as the milky white sap can cause skin irritation.  

VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.

 

 

 

Profile Video:
See this plant in the following landscape:
Retaining Wall Garden
Cultivars / Varieties:
  • Arkansas Amsonia
  • Blue Star
Arkansas Amsonia, Blue Star
Tags:
#showy flowers#rain garden#fine texture#blue flowers#low maintenance#fall interest#cottage garden#rabbit resistant#mass planting#deer resistant#herbaceous perennial#rock garden#butterfly friendly#HS302#landscape plant sleuths course#woodland#cpp
 
Cultivars / Varieties:
  • Arkansas Amsonia
  • Blue Star
Arkansas Amsonia, Blue Star
Tags:
#showy flowers#rain garden#fine texture#blue flowers#low maintenance#fall interest#cottage garden#rabbit resistant#mass planting#deer resistant#herbaceous perennial#rock garden#butterfly friendly#HS302#landscape plant sleuths course#woodland#cpp
  • Attributes:
    Genus:
    Amsonia
    Species:
    hubrichtii
    Family:
    Apocynaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Stem Cutting
    Country Or Region Of Origin:
    Arkansas to Oklahoma
    Distribution:
    South Central US
    Wildlife Value:
    ​​​​​​​  Flowers attract butterflies.  Is deer resistant.
    Play Value:
    Attractive Flowers
    Attracts Pollinators
    Dimensions:
    Height: 2 ft. 0 in. - 3 ft. 0 in.
    Width: 2 ft. 0 in. - 3 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Clumping
    Erect
    Growth Rate:
    Slow
    Maintenance:
    Low
    Texture:
    Fine
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Sand
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Dry
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
  • Fruit:
    Fruit Color:
    Brown/Copper
    Display/Harvest Time:
    Summer
    Fruit Type:
    Follicle
    Fruit Length:
    1-3 inches
    Fruit Width:
    < 1 inch
    Fruit Description:
    Attractive, narrow beanlike pods form after flowering.
  • Flowers:
    Flower Color:
    Blue
    White
    Flower Inflorescence:
    Umbel
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Spring
    Flower Shape:
    Star
    Flower Petals:
    4-5 petals/rays
    Flower Size:
    < 1 inch
    Flower Description:
    Terminal clusters of 1/2 inch blue star-shaped flowers occur in spring
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Gold/Yellow
    Green
    Leaf Feel:
    Soft
    Leaf Value To Gardener:
    Showy
    Deciduous Leaf Fall Color:
    Gold/Yellow
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Linear
    Oblong
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    1-3 inches
    Leaf Width:
    < 1 inch
    Leaf Description:
    The soft, needle-like leaves become a beautiful golden fall color when grown in full sun. They are very narrow and 2-3 inches long.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    Green branched stems. Have a milky sap when broken
  • Landscape:
    Landscape Location:
    Coastal
    Naturalized Area
    Patio
    Slope/Bank
    Walkways
    Woodland
    Landscape Theme:
    Cottage Garden
    Pollinator Garden
    Rain Garden
    Rock Garden
    Design Feature:
    Accent
    Border
    Mass Planting
    Small groups
    Specimen
    Attracts:
    Butterflies
    Resistance To Challenges:
    Deer