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Plants that fill a similar niche:
Hibiscus laevis
Passiflora incarnata
Rhododendron atlanticum
Crinum americanum has some common insect problems:
Banded Greenhouse Thrips

Southern Swamp Lily Crinum americanum

Other plants called Southern Swamp Lily:

Previously known as:

  • Bulbine uncinata
  • Crinum americanum var. traubii
  • Crinum floridanum
  • Crinum longiflorum
  • Crinum strictum var. traubii
Phonetic Spelling
KRY-num a-mer-ih-KAY-num
This plant has low severity poison characteristics.
See below
Description

Southern swamp lily is a herbaceous perennial bulb in the onion family (Amaryllidaceae), found in wetlands, swamps, marshes, and stream banks from South Carolina to Florida and west to the Gulf coast of Texas. It is an erect plant, growing up to 2 to 3 feet tall, and forms small clumps. Its leaves grow directly from the bulb and are narrow, green, strap-like. The flowers bloom from June to September, and are delicate, fragrant, white, and lily-like with a blush of pink. Two to six trumpet-shaped flowers form into a showy umbel at the top of the distinctively reddish stem. The genus name, Crinum, originates from the Greek word krinon, meaning lily. The specific epithet, americanum, refers to its native habitat. 

Prefers full sun to partial shade and rich, wet, slightly acidic soils of sand, loam, or clay. Although it is native to wet sites, it will grow in moist garden environments or in containers kept moist to wet. Only use a pot 2 inches larger than the bulb. If growing in the garden, mulch heavily in the winter. Otherwise, it can be grown in water gardens or along streams, ponds, or bogs. Do not disturb the bulbs once planted, or it may take up to 2 to 3 years before it blooms again. Propagated by division or seeds. Divided plants will bloom more quickly than offshoot bulbs. 

Each bulb is thick and fleshy, measuring 3 to 4 inches in diameter, and has a tapered neck. The flowers have sepals, measuring 3 to 4 inches long, joined at the base to form a long tube. The sepals curve backward to form a somewhat ball-like form. The purple stamens and anthers extend outward from the blossom. The blooms attract hummingbirds, bees, butterflies, and moths.

Consider for use as a border, foundation planting in moist to wet areas of your landscape. They may also be grown in containers for the patio. Ideal for water gardens or bogs. Provides a good cutting flower for floral arrangements.

Insects, Diseases, and Other Plant Problems: Monitor for mealybugs, spider mites, nematodes, slugs, and snails. Grasshoppers are known to chew on the plant's leaves. Potential diseases include red blotch fungus and crinum mosaic potyvirus. Leaf scorch may occur. 

More information on Crinum.

See this plant in the following landscape :
Water Garden at David Caldwell Historic Park
Cultivars / Varieties:
  • 'St. Marks'
    up to 20 inches tall, hardy 7a to 10b, glossy, dark green foliage, fragrant, white flowers
'St. Marks'
Tags:
#hummingbird friendly#bulb#showy flowers#water garden#fragrant flowers#white flowers#interiorscape#stream banks#herbaceous#swamps#large flowers#long bloom time#pollinator plant#larval host plant#food source summer#food source fall#Coastal OBL#food source herbage#food source nectar#food source pollen#wet soils tolerant#butterfly friendly#problem for cats#problem for dogs#bee friendly#problem for children#Audubon#container plant#poisonous if ingested#perennial#boggy sites#moth friendly#pond
 
Cultivars / Varieties:
  • 'St. Marks'
    up to 20 inches tall, hardy 7a to 10b, glossy, dark green foliage, fragrant, white flowers
'St. Marks'
Tags:
#hummingbird friendly#bulb#showy flowers#water garden#fragrant flowers#white flowers#interiorscape#stream banks#herbaceous#swamps#large flowers#long bloom time#pollinator plant#larval host plant#food source summer#food source fall#Coastal OBL#food source herbage#food source nectar#food source pollen#wet soils tolerant#butterfly friendly#problem for cats#problem for dogs#bee friendly#problem for children#Audubon#container plant#poisonous if ingested#perennial#boggy sites#moth friendly#pond
  • Attributes:
    Genus:
    Crinum
    Species:
    americanum
    Family:
    Amaryllidaceae
    Life Cycle:
    Bulb
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    Southeastern United States to Mexico and the West Caribbean
    Distribution:
    Native: United States--Alabama, Florida, Georgia, Louisiana, Mississippi, South Carolina, and Texas; Cayman Islands, Jamaica, Mexico Central, Mexico Gulf, Mexico Southeast, and Mexico Southwest. Introduced: Cuba
    Wildlife Value:
    Submerged portions provide habitats for many micro and macroinvertebrates. These invertebrates, in turn, are used as food by fish and other wildlife (e.g., amphibians, reptiles, ducks, etc.). After aquatic plants die, their decomposition by bacteria and fungi provides food (called “detritus”) for many aquatic invertebrates. Attracts moths at night with increased fragrance. It also attracts hummingbirds, bees and butterflies. Pollinated by sphinx moths. Larval host of the Spanish moth.
    Dimensions:
    Height: 2 ft. 0 in. - 3 ft. 0 in.
    Width: 1 ft. 0 in. - 2 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Bulb
    Herbaceous Perennial
    Poisonous
    Water Plant
    Habit/Form:
    Clumping
    Erect
    Growth Rate:
    Rapid
    Maintenance:
    Low
    Texture:
    Medium
  • 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
    High Organic Matter
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Frequent Standing Water
    Moist
    Occasionally Wet
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    USDA Plant Hardiness Zone:
    8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
  • Fruit:
    Fruit Color:
    Brown/Copper
    Green
    Display/Harvest Time:
    Fall
    Summer
    Fruit Type:
    Capsule
    Fruit Length:
    1-3 inches
    Fruit Width:
    1-3 inches
    Fruit Description:
    The fruit is a green capsule initially and turns brown as it ripens. It is round, smooth, firm, measuring 1 to 2 inches in diameter, with large, fleshy seeds. Each seed pod contains 4 to 5 seeds.
  • Flowers:
    Flower Color:
    Pink
    White
    Flower Inflorescence:
    Umbel
    Flower Value To Gardener:
    Fragrant
    Good Cut
    Long Bloom Season
    Showy
    Flower Bloom Time:
    Fall
    Summer
    Flower Shape:
    Trumpet
    Flower Petals:
    Colored Sepals
    Flower Size:
    3-6 inches
    Flower Description:
    Large lily-like flowers are up to 4 inches across and long, and appear in umbels of 2 to 6. They have long, narrow sepals, measuring 0.5 inches wide, that curve backwards. The sepals measure 3 to 4 inches long and join at the base to form a long tube. They are white with a blush of pink, and the long purple stamens and anthers extend outward beyond the sepals. Blooms from June to September.
  • Leaves:
    Leaf Color:
    Green
    Leaf Feel:
    Glossy
    Leathery
    Leaf Type:
    Simple
    Leaf Shape:
    Lanceolate
    Linear
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Width:
    1-3 inches
    Leaf Description:
    Long green strap-like leaves are 18 inches to 36 inches long, 2 to 3 inches wide, and arise directly from the bulb. Each leaf is simple, linear, with entire margins.
  • Stem:
    Stem Color:
    Green
    Red/Burgundy
    Stem Is Aromatic:
    No
    Stem Description:
    The long reddish-green stem is erect, unbranched, smooth, and 1 inch in diameter. It arises directly from the bulb and has no leaves attached.
  • Landscape:
    Landscape Location:
    Container
    Patio
    Pond
    Riparian
    Landscape Theme:
    Cutting Garden
    Rain Garden
    Water Garden
    Design Feature:
    Accent
    Mass Planting
    Small groups
    Specimen
    Attracts:
    Bees
    Butterflies
    Frogs
    Hummingbirds
    Moths
    Pollinators
    Songbirds
    Resistance To Challenges:
    Deer
    Rabbits
    Wet Soil
    Problems:
    Poisonous to Humans
    Problem for Cats
    Problem for Children
    Problem for Dogs
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    If ingested, may cause nausea, stomach pain, vomiting and diarrhea.
    Poison Toxic Principle:
    Alkaloids
    Causes Contact Dermatitis:
    No
    Poison Part:
    Flowers
    Leaves
    Roots
    Sap/Juice
    Seeds
    Stems