FNPS Plant Database

Seymeria spp

blacksenna
  • Photo by: John Lampkin, Nature Coast FNPS
  • Photo by: John Lampkin, Nature Coast FNPS
  • Photo by: Shirley Denton, Suncoast Chapter FNPS

Nomenclature

Common Name:

blacksenna

Synonym(s):

Seymeria pectinata, Seymeria cassioides

Genus species:

Seymeria spp

Family:

Orobanchaceae

Plant Specifics

Form:

Flower

Size:

3–4 ft

Life Span:

Long-lived perennial

Flower Color:

yellow

Fruit Color:

Phenology:

Spring-fall (mostly fall) blooming. Winter dormant

Noted For:

Landscaping

Recommended Uses:

Retain in semi-natural gardens.

Considerations:

Both species are hemi-parasitic (semi-parasitic) and difficult to grow without appropriate host plants.

Availability:

Propagation:

Seed. Please be sure to have landowner permission before collecting.

Light:

Moisture Tolerance:

Always Flooded---------------------------------Extremely Dry

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Somewhat moist, no flooding -to- Very long very dry periods

Salt Water Flooding Tolerance:

Unknown

Salt Spray/Salty Soil Tolerance:

Low/no tolerance of salty wind or direct salt spray

Soil or Other Substrate:

Soil pH:

Suitable to Grow In:

USDA zones are based on the average annual extreme minimum winter temperature.

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Vouchered In:

Distribution
Vouchered
Not vouchered
Selected
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No county distribution is available for this plant yet.
Starting…
Map coded by Melissa Fernandez-de Cespedes (Paynes Prairie Chapter)

Ecology

Wildlife:

Pollinators, Caterpillars

Larval host for black buckeye. Attracts insects.

Native Habitats:

Open upland woods and disturbed edges

Natural Range in Florida:

Comments:

Ethnobotany:

General Comments:

They are included here because they are valuable to insects and because they are lovely and good to have in a native garden if you are lucky enough to have them naturally. Data on culture has been assumed from where this grows in nature -- it is not typically grown and no reliable data appears to be available. Can parasatize southern pines leading, in heavy infestations, to loss of vigor.
FNPS Plant Print

Citations:

Huegel, Craig N. (2009-2025). Native Florida Wildflowers (blog). ( http://hawthornhillwildflowers.blogspot.com/ ).


Univ. of Georgia Marine Extension Service. Coastscapes - Native Plant Database. ( https://ecoscapes.bugwood.org/plant.cfm?code=SEPE2 ). Accessed 2026. Marine Extension Service, University of Georgia, Brunswick, GA.

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