How lovely, the wafting light scent of vanilla that these showy purple flowerspikes exude while walking along shaded trails across Florida. Take the time to stop and appreciate the profound beauty of this native shrub, and take a good, long sniff. The crushed leaves are also fragrant. This plant is host to three of our native butterflies, the Silver-Spotted Skipper, Gray Hairstreak, and Southern Dogface. It is also a pollinator magnet, attracting many insects to partake of its nectar, as well as hummingbirds. For this reason, native plant expert Craig Huegel appropriately refers to this plant as "Florida's Butterfly Bush." The seeds have been described as edible by some resources, but I caution against eating them. See my "caution" below.
CAUTION: DO NOT CONSUME: Although the seeds are listed as being edible on some websites, I would not recommend consuming them. Many seeds of Fabaceae species contain toxic compounds. Without proper accredited documentation, they should be considered toxic in my opinion. LIVESTOCK CAUTION: “Livestock browsing the shrub are poisoned.” CONSERVATION: It is ranked as "imperiled" in South Florida ["IRC South Florida Status"], so do not harvest from it or dig plants in the southern part of the state for this reason.
EDIBILITY: SEE CAUTION ABOVE - DO NOT CONSUME: The seeds are said to be used as a spice and are "crushed as a condiment." At least three sources claim that “the crushed fruit is used as a condiment.” (Tanaka's Encyclopedia of Edible Plants of the World, Kunkel’s Plants for Human Consumption, & Cornucopia). Green Deane mentions the Cornucopia reference.
MEDICINAL USES: According to Florida Ethnobotany, Florida Seminoles used the roots (mixed with other herbs) against “moving sickness”, “a general malaise with a pain that moved from one area of the body to another.” The Oklahoma Seminoles used the leaves and stems as medicine, boiled into a tea, as a general tonic. The Meskwaki and Pawnee also used it as medicine.
EXTERNAL MEDICINAL USES: According to Sturtevant, parts were chewed and applied to treat rheumatic pain.
CHEMICAL CONSTITUENTS: It “contains cannabinoid-like compounds” and rotenoids.
DYE PLANT: There was “widespread use” of Amorpha species by indigenous people as a blue dye. It “produced a blue dye, although some say it was inferior to true indigo.” “The pigment is only present in very small quantities.”
CORDAGE?: - The odor of the retted plants is said to be “particularly offensive.”
INSECT REPELLANT: “Resinous pustules on the plant contain 'amorpha', a contact and stomachic insecticide that also acts as an insect repellent.“
ARROW SHAFTS: Known as Mon-ca hi to the Osage, meaning arrow shaft stalk. The Seminoles and Lakota “used the stems to make arrows.”
MATS, RUGS, AND BEDDING: The Kiowa used the long stems “as a foundation for bedding material.” Also, “stems were made into mats, rugs, and bedding.”
WINDBREAK, EROSION CONTROL: Planted as a windbreak, and to prevent soil erosion.
NITROGEN FIXER: It forms root nodules and fixes nitrogen.
WATER PLANT: "Bog, water garden." 
LIVESTOCK - CAUTION: “Livestock browsing the shrub are poisoned.”
- HUMMINGBIRD ATTRACTANT: According to the Native Plant Society of Texas, Houston Chapter, hummingbirds nectar at the flowers.  I have only occasionally witnessed this in the wilds of Florida.
- BUTTERFLY ATTRACTANT: The flowers attract many butterflies, bees, and other pollinators. Host plant to Silver-Spotted Skipper (Epargyreusclarus), Gray Hairstreak (Strymonmelinus), and Southern Dogface (Zerenecesonia) butterfly caterpillars. Craig Huegel writes, “I like to think of this species as Florida's "butterfly bush" as it has many of the same qualities as a Buddleia, and performs much better here.” It "makes a great native substitute for Butterfly Bush." 
- BEES: "The flowers are pollinated by various kinds of bees." 
- BIRD FORAGE: Ripe seeds are eaten by doves & other birds.
- DEER: "Deer resistant." 
- ORNAMENTAL: The showy flowers make a lovely display in native and informal plantings.
NATIVE TO: "Widespread in North America, including northern Mexico."  Pennsylvania to Minnesota & Saskatchewan, south to Florida & Chihuahua, Mexico. Considered by some to be invasive in the eastern & middle states. "
HABITAT: Near streams & rivers in rich moist thickets, half sunny, damp woodland edges, etc. "Coastal Strand, disturbed upland, floodplain forest, marl prairie, mesic flatwoods, mesic hammock."  Also in open fields, along streams and other bodies of water, and moist meadows. 
DESCRIPTION: Multi-trunked, perennial, deciduous, "loose," "airy" shrub.
CONSERVATION: Regional Conservation lists it as "imperiled" under its "IRC South Florida Status."  IRC South Florida Status: Imperiled
- HEIGHT: 5-15 (rarely 20) feet high. "Typically 6' tall." 
- SPREAD: "Spread 10-15 feet." 
- RATE OF GROWTH: Fast growing. 
- LEAVES: Leaves pinnately-compound, "each with 13-33 oval or oblong leaflets, around a foot long [in total]" , finely-textured, feathery. "Individual leaflets are 1-2" long and about a half inch wide."  Deciduous. Fragrant when crushed. 
- FLOWERS: Flowers brilliant purple, in spires/spikes around 6" long , which rise erect, usually above the foliage, flowers are lightly fragrant (vanilla-like), and are quite beautiful, to say the least. Take a look at a single flower with a magnifying glass... notice a single petal with ten stamens.  They have "conspicuous [bright] orange anthers, extending well beyond the petal." 
- FLOWERING SEASON: "Flowers bloom from April to June." 
- SEEDS: Flattened seedpods 0.25" long.  "Each containing 1-2 seeds."  Ripen July through August. "The pods have tiny dot-like glands." 
CULTURE: Cultivated and planted widely. Sold and cultivated in Europe as early as the 1700s. Casts a light shade, so other plants may be grown beneath it. Avoid root disturbance after planting. “It can be maintained as a single trunk shrub.”
- HARDINESS: Zones 4-9.  Other sources list it southward to zone 10.
- LIGHT: Does best in partial sun, good in full sun. 
- SOIL: Average. 
- SALT TOLERANCE: "Tolerates saline soil." 
- WATER: Likes regular watering. Drought tolerant. It "does not like extended periods of drought." 
- PROPAGATION: Easy to grow from seed (germinates in 1-2 months). Also by half-ripe and mature cuttings, suckers, and layers. Floridata writes, "Rooted suckers from the base of the plant can be separated to start new plants. Stem tips can be rooted fairly easily. Seeds have a hard coating and can take a long time to germinate. Still, false indigo can self seed and may even form a thicket." 
- WIND: Wind tolerant.
- INSECT RESISTANT: Very insect resistant.
- PRUNING: "Prune false indigo in late winter or early spring to maintain a pleasing shape, otherwise it tends to get leggy and sloppy." 
- CULTIVARS: There are a number of named, cultivated forms. "A handful of cultivars have been selected. A weeping form, ‘Pendula’; a white flowered form, ‘Albiflora’; and one with crinkled leaves, ‘Crispa’ are listed." 
When to Prune
When to Harvest
Sources for acquiring
Potted plants are available at a few native nurseries statewide.
 abnatives.com [American Beauties Native Plants]
 Aldo De Bastiani
 Arlene Ripley
 David Spicer
 Flora of North America
 Florida Ethnobotany
 Go Botany Blog
 Hawthorne Hill
 Jeffrey Pippen
 Kunkel’s Plants for Human Consumption, & Cornucopia
 Native Plant Society of Texas - Houston Chapter
 Patricia Ferrari
 Rancho Santa Ana Botanic Garden
 Regional Conservation
 Tanaka's Encyclopedia of Edible Plants of the World
 USDA Plant Database
 Wildflowers Blog
- 23 in all.