Pencil Flower has been called 'the cutest flower in all the land'. Its genus is derived from the Greek stylo and anthos which translates to style flower. That in turn refers to the stalk-like calyx tube that is surrounding the pistil of the flower. The common name pencil flower is also derived from the plant structure, resembling the wood on a pencil surrounding the lead. It is a native perennial wildflower in the legume family found in central and eastern USA in dry woods, fields and thickets. It is found throughout NC. The plant grows .5 to 1.5 feet tall and the yellow pea-like flowers bloom from late spring to fall, but rather sparsely. Bees pollinate the flowers and deer and rabbits will browse the leaves. It also serves as a host plant for the larvae of the Barred yellow ( Eurema daira ) butterfly. There is some variation in the leaves and flowers throughout its range. This plant prefers acidic somewhat nutrient poor soils where competition from other plants is not an issue. Like other plants in the legume family, it has the ability to make its own nitrogen, thereby surviving where other plants may not. It grows in full sun to partial shade and is generally found in upland rocky woodlands and savannas, bluffs, prairies, fields and particularly where sandstone is present close to the ground surface. It is generally not used in cultivation and is hard to find but could be grown in naturalized areas. It is sometimes confused with Desmodium and Lespedeza . The difference is in the veins on the underside of the leaflets. On Stylosanthes biflora , the veins are lighter in color than the leaflet, while the veins on Lespedeza and D esmodium are the same color as the leaflets.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
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; Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist | Occasionally Dry
Available space
Less than 12 inches
NC region
Coastal; Mountains; Piedmont
Growth rate
Rapid
Maintenance
Medium
Canopy layer
6 - Vine (vertical)
Form & Appearance
Habit / form
Ascending; Climbing; Erect; Horizontal
Texture
Medium
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Alternate
Leaf shape
Elliptical; Lanceolate
Leaf margin
Entire
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
Compound leaves with 3 leaflets. The upper surface is medium green while the undersides are paler with short hairs. Leaflets are .5 to 1.5 inches long and oval. Veins on the upper leaf surface may appear to be shiny.
Flower color
Gold/Yellow; Orange
Flower value
Long Bloom Season
Flower form
Head; Solitary
Flower shape
Irregular
Flower size
< 1 inch
Flower detail
Small pea-like flowers with 5 yellow petals growing singly or in small clusters at the end of the branches. Flowers late spring through fall.
Bloom time
Fall; Spring; Summer
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Small seedpods will appear after the flowers bloom. Each has two segments. The first is infertile while the second contains one seed.
Stem color
Green
Stem detail
It has bristle-tipped, thin, wiry stems, and is branched at the base and also above the base. They can be found standing erect, climbing or in a horizontal position.
Wildlife & Ecology
Native status
Native
Origin
Central & Eastern U.S.A
Distribution
AL , AR , AZ , DC , DE , FL , GA , IL , IN , KS , KY , LA , MD , MO , MS , NC , NJ , NY , OH , OK , PA , SC , TN , TX , VA , WV
Wildlife value
Host plant to Barred Yellow butterfly. Deer, quail, turkeys and rabbits are attracted to the foliage.
Attracts
Bees; Butterflies; Pollinators; Small Mammals; Specialized Bees