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Mountain Laurel Kalmia latifolia

Other plants called Mountain Laurel:

Phonetic Spelling
KAL-mee-ah lah-tih-FOH-lee-ah
This plant has high severity poison characteristics.
See below
Description

Mountain laurel is a broadleaf, evergreen shrub or small tree in the Ericaceae (blueberry) family that is native to eastern North America, where it is found in a variety of habitats, including open rocky or sandy woods, cool meadows, balds, mountain slopes, acidic forests, and woodland margins. It can grow slowly to 6 to 10 feet tall as a dense, rounded shrub, opening up and developing gnarly branches with age. Rarely it will grow to 32 feet tall as a small tree, particularly on slopes in the Appalachian Mountains. Linnaeus named the genus after Swedish botanist Peter Kalm (1716-1779), who explored plant life in parts of eastern North America from 1747 to 1751. 

Mountain laurel tolerates a wide range of light conditions, from full sun to full shade, but grows best in partial shade (morning sun with early to mid-afternoon shade) and in cool, moist, acidic, humus-rich, well-drained soils. Mulch to retain moisture and keep root zones cool. The plant does not grow well in heavy clay soils or wet soils. In heavy soils, raised plantings should be considered to promote better drainage. Remove spent flower clusters immediately after bloom and prune branches back lightly after bloom to promote bushy growth. When pruning, keep in mind that next year's blossoms will appear on old growth.

It is the state flower of Connecticut. It blooms in late spring to early summer, and its buds and fruits are showy. Attractive foliage makes this a good choice for year-round interest. Flowers have touch-sensitive anthers contained in pockets in the corolla, which triggers the release of pollen when pollinators like bees visit. There are many cultivars available, including some that are heat tolerant and even some that are dwarf varieties. Plant mountain laurel in a meadow, naturalized, or woodland area, and use it as an accent or flowering shrub in a native, children’s, butterfly, or pollinator garden.

Fire Risk: This plant has a high flammability rating and should not be planted within the defensible space of your home. Select plants with a low flammability rating for the sites nearest your home. 

Quick ID Hints:

  • Evergreen shrub with sympodial growth and elliptic leaves
  • Fruit, buds, or inflorescence is visible year round
  • Terminal clusters of bell-shaped flowers are present in the late spring
  • Flowers have inner purple markings and 10 anther pockets
  • Old trunks and limbs are gnarly, cracked, and crooked

Insects, Diseases, and Other Plant Problems: Mountain laurel is susceptible to borers, scale, white fly, and lace bugs. It is also susceptible to leaf spots and blights. While the nectar poses no problems for bees, if honey bees feed heavily on these plants, they are known to produce "mad honey" that can be toxic for human consumption. 

See this plant in the following landscape:
Cultivars / Varieties:
'Bullseye', 'Carol', 'Carousel', 'Elf', 'Keepsake', 'Minuet', 'Olympic Fire', 'Pink Charm', 'Pristine', 'Richard Jaynes', 'Sarah', 'Snowdrift'
Tags:
#contorted trunk#hummingbird friendly#evergreen#poisonous#interesting bark#native shrub#cover plant#dwarf#fire high flammability#NC native#deer browsing plant#children's garden#native garden#playground plant#naturalizes#pollinator plant#fantz#flowers late spring#flowers early summer#food source herbage#food source nectar#food source pollen#bird friendly#nectar plant late spring#food source hard mast fruit#mammals#butterfly friendly#nectar plant early summer#nectar plant midspring#Piedmont Mountains FACU#Coastal FACU#problem for cats#problem for dogs#problem for horses#Audubon#poisonous nectar#flowers midspring#wildlife friendly#cpp
 
Cultivars / Varieties:
'Bullseye', 'Carol', 'Carousel', 'Elf', 'Keepsake', 'Minuet', 'Olympic Fire', 'Pink Charm', 'Pristine', 'Richard Jaynes', 'Sarah', 'Snowdrift'
Tags:
#contorted trunk#hummingbird friendly#evergreen#poisonous#interesting bark#native shrub#cover plant#dwarf#fire high flammability#NC native#deer browsing plant#children's garden#native garden#playground plant#naturalizes#pollinator plant#fantz#flowers late spring#flowers early summer#food source herbage#food source nectar#food source pollen#bird friendly#nectar plant late spring#food source hard mast fruit#mammals#butterfly friendly#nectar plant early summer#nectar plant midspring#Piedmont Mountains FACU#Coastal FACU#problem for cats#problem for dogs#problem for horses#Audubon#poisonous nectar#flowers midspring#wildlife friendly#cpp
  • Attributes:
    Genus:
    Kalmia
    Species:
    latifolia
    Family:
    Ericaceae
    Life Cycle:
    Woody
    Country Or Region Of Origin:
    Eastern U.S.A
    Distribution:
    New England south to the southern Indiana, Louisiana and the Florida panhandle
    Fire Risk Rating:
    high flammability
    Wildlife Value:
    It provides winter cover. Hummingbirds, butterflies and other pollinators are attracted to the flowers. Although the foilage is toxic to domestic livestock, white-tailed deer browse the leaves and twigs during the winter and early spring.
    Play Value:
    Wildlife Food Source
    Particularly Resistant To (Insects/Diseases/Other Problems):
    Highly resistant to damage from deer.
    Dimensions:
    Height: 4 ft. 0 in. - 15 ft. 0 in.
    Width: 4 ft. 0 in. - 8 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Native Plant
    Perennial
    Poisonous
    Shrub
    Woody Plant Leaf Characteristics:
    Broadleaf Evergreen
    Habit/Form:
    Dense
    Multi-stemmed
    Open
    Rounded
    Texture:
    Medium
  • Cultural Conditions:
    Light:
    Dappled Sunlight (Shade through upper canopy all day)
    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:
    High Organic Matter
    Loam (Silt)
    Sand
    Shallow Rocky
    Soil pH:
    Acid (<6.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Dry
    Available Space To Plant:
    6-feet-12 feet
    12-24 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Fruit Color:
    Brown/Copper
    Display/Harvest Time:
    Fall
    Fruit Type:
    Capsule
    Fruit Length:
    < 1 inch
    Fruit Width:
    < 1 inch
    Fruit Description:
    Plant produces 5-valved, dihiscent capsules (3/16") that are non-showy and brown in color that persist into winter. Fruits are available from September to October.
  • Flowers:
    Flower Color:
    Pink
    Purple/Lavender
    White
    Flower Inflorescence:
    Corymb
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Spring
    Summer
    Flower Shape:
    Saucer
    Flower Petals:
    4-5 petals/rays
    Flower Size:
    < 1 inch
    Flower Description:
    Flowers appear terminal clusters (corymbs 4" to 6” in diameter), typically covering the shrub in late April-July for several weeks with an often exceptional bloom. Each flower (to 1” across) is cup-shaped with five sides and ranges in color from rose to white with purple markings inside of the corolla. There are 5 calyx lobes that are corolla campanulate. 5 lobes are pleated with 10 anthers that emerge at bloom (stamens included) but are at first tucked in small pockets.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Broadleaf Evergreen
    Leaf Color:
    Green
    Leaf Feel:
    Glossy
    Leathery
    Leaf Value To Gardener:
    Long-lasting
    Showy
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Opposite
    Whorled
    Leaf Shape:
    Elliptical
    Lanceolate
    Oblanceolate
    Hairs Present:
    No
    Leaf Length:
    3-6 inches
    Leaf Width:
    < 1 inch
    Leaf Description:
    The Mountain laurel has elliptic to lanceolate or oblanceolate, simple, alternate, acute to short acuminate, cuneate, coriacious, entire, leathery, and congested glossy evergreen leaves (2" to 5” long) which are dark green above and yellow-green beneath and reminiscent to the leaves of rhododendrons. The leaves are occasionally opposite or whorled. New growth is yellow-green, yellows with age and falls off.
  • Bark:
    Bark Description:
    The bark is thin, smooth and dark red-brown in color in young trees. The barks shreds and splits as the tree ages. The trunk is contorted with cinnamon bark.
  • Stem:
    Stem Color:
    Brown/Copper
    Green
    Red/Burgundy
    Stem Is Aromatic:
    No
    Stem Description:
    Stems are sympodial and initially bronze and sticky. As they mature, they turn turn red green or brown and become crooked and gnarly. Epidermis and gray-brown bark crack to reveal lighter colors in older stems. Pith is solid and light green.
  • Landscape:
    Landscape Location:
    Coastal
    Meadow
    Naturalized Area
    Recreational Play Area
    Woodland
    Landscape Theme:
    Butterfly Garden
    Children's Garden
    Native Garden
    Pollinator Garden
    Design Feature:
    Accent
    Flowering Tree
    Shade Tree
    Attracts:
    Butterflies
    Hummingbirds
    Pollinators
    Small Mammals
    Resistance To Challenges:
    Compaction
    Deer
    Problems:
    Poisonous to Humans
    Problem for Cats
    Problem for Dogs
    Problem for Horses
  • Poisonous to Humans:
    Poison Severity:
    High
    Poison Symptoms:
    The toxic principle interferes with normal skeletal muscle, cardiac muscle, and nerve function. Clinical effects typically occur within a few hours after ingestion, and can include acute digestive upset, excessive drooling, loss of appetite, frequent bowel movements/diarrhea, colic, sweating, abdominal pain, depression, weakness, loss of coordination, stupor, watering of eyes and nose, nausea, cardiac failure, vomiting, leg paralysis, weak heart rate, and recumbency for 2 or more days; at this point, improvement may be seen or the animal may become comatose and die. Typically not very palatable to horses unless it is the only forage available, but sheep and goats may graze readily on the plant.
    Poison Toxic Principle:
    Andromedotoxin, a resinoid; arbutin, a glycoside, Grayanotoxins
    Causes Contact Dermatitis:
    No
    Poison Part:
    Bark
    Flowers
    Fruits
    Leaves
    Roots
    Seeds
    Stems