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Berteroa incana

Phonetic Spelling
ber-TER-oh-a in-KAN-nuh
Description

Hoary alyssum is a biennial that can be a short-lived perennial or annual wildflower in the mustard family (Brassicaceae).  It is native to Europe and Asia and has spread to other countries in contaminated crop seeds. It is now found in all states except the southernmost. It is an aggressive invader in fields, rangeland, pastures and other disturbed sites and is listed as a noxious weed in several states.

Hoary alyssum grows in full sun, tolerates alkaline and infertile soils and prefers well-drained sandy or rocky soils. It will grow 1 to 3 feet tall and can produce seeds throughout the summer.

It has delicate white blooms that appear in clusters in mid-spring through early fall. The leaves have a gray-green color due to the dense star-shaped hairs present. Young plants have a basal rosette of leaves that often die down when flowering occurs, leaving stem leaves. Stems are also densely hairy.

Control is by hand pulling or tilling until the seed bank has been depleted. There is no successful chemical control. It is a problem for horses in a field.

Insects, Diseases, and Other Plant Problems:  No significant problems. Root rot can occur in poorly drained soils.

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#white flowers#seeds#problem for horses#non-toxic for dogs#non-toxic for cats#annual#short lived#weedy
 
Cultivars / Varieties:
Tags:
#white flowers#seeds#problem for horses#non-toxic for dogs#non-toxic for cats#annual#short lived#weedy
  • Attributes:
    Genus:
    Berteroa
    Species:
    incana
    Family:
    Brassicaceae
    Life Cycle:
    Annual
    Biennial
    Perennial
    Recommended Propagation Strategy:
    Seed
    Country Or Region Of Origin:
    Europe, China
  • Whole Plant Traits:
    Plant Type:
    Annual
    Perennial
    Wildflower
    Growth Rate:
    Rapid
    Maintenance:
    High
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Soil Texture:
    Loam (Silt)
    Sand
    Shallow Rocky
    Soil pH:
    Alkaline (>8.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Occasionally Dry
  • Fruit:
    Fruit Color:
    Green
    Fruit Type:
    Capsule
    Fruit Length:
    < 1 inch
    Fruit Description:
    The fruit is a round, flat pod ¼ inch long with the style persistent at the tip and contains many seeds. They are spaced along the length of the elongated branching stems.
  • Flowers:
    Flower Color:
    White
    Flower Inflorescence:
    Raceme
    Flower Bloom Time:
    Fall
    Spring
    Summer
    Flower Shape:
    Star
    Flower Petals:
    4-5 petals/rays
    Flower Size:
    < 1 inch
    Flower Description:
    Long racemes of small 4 petaled flowers with 6 yellow-green stamens. The petals are deeply lobed giving the impression of 8 petals. Clusters are 1-2 inches across. Blooms until frost.
  • Leaves:
    Leaf Color:
    Gray/Silver
    Green
    Leaf Feel:
    Velvety
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Rosulate
    Leaf Shape:
    Linear
    Oblanceolate
    Leaf Margin:
    Entire
    Hairs Present:
    Yes
    Leaf Length:
    1-3 inches
    Leaf Width:
    < 1 inch
    Leaf Description:
    1½ to 3 inches long, up to ½ inch wide, toothless, alternate leaves have a pointed or blunt tip and are stalkless. The dense star-shaped hairs give them a grayish-green color. Young plants have a basal rosette of leaves that typically wither away by flowering time. Basal leaves are hairy, oblanceolate and up to 3 inches long with smooth to slightly wavy margins and long stalks
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Surface:
    Hairy (pubescent)
    Stem Description:
    Single or multi-stem densley hairy.
  • Landscape:
    Problems:
    Problem for Horses
    Weedy