Violet Tree

Scientific name: Phlebotaenia cowellii

POWO Status: Not listed.

It is a rare tree found at low to middle elevations in the U.S. Virgin Islands. Specifically, it’s a tree that can grow to a height of 30 to 40 feet, according to the Center for Plant Conservation.

IUCN Red List threat level: Near Threatened

GPS Location: 17° 42′ 59.89″ N, 64° 49′ 49.60″ W

Medicinal Uses

In traditional medicine, a tea made from the flowering shrub Phlebotaenia cowellii (also known as Polygala cowellii or Cowell’s Phlebotaenia) has been used to treat various ailments.

Specific traditional medicinal uses include:

Fever
Headache
Stomach problems

Phlebotaenia cowellii is native to Central and South America, including Puerto Rico, where it is known as “Palo de Violeta”. In addition to its traditional medicinal uses, it is also cultivated as an ornamental plant.

Observations:

Phenological Markers – Violet Tree (Phlebotaenia cowellii)

Common Name: Violet Tree
Scientific Name: Phlebotaenia cowellii
Family: Polygalaceae
Origin: Caribbean native (notably Puerto Rico and Hispaniola)
Form: Shrub or small tree, 1–3 meters in height, multi-stemmed habit

Annual Phenological Cycle

Phenophase	Typical Timing (St. Croix – Lowland Tropical)	Field Notes
Leaf Flush	April – June	Fresh foliage appears at the start of the rainy season. New leaves are light green and thin.
Flowering	July – October	Small, violet to reddish-purple flowers emerge in loose clusters.
Fruit Development	August – November	Flat, dry seed capsules follow flowering. May persist on branches into dry season.
Leaf Drop (Partial)	February – March (dry season)	Partial deciduousness observed during dry spells; may retain core canopy.
Dormancy	March – April (minimal growth)	Growth pauses briefly before wet season flush.

Identification Notes

Bark is smooth, grey-brown.
Flowers have a distinct violet hue, giving rise to the common name.
Typically found in disturbed habitats or limestone scrub.
Rare in cultivation but of interest for conservation plantings.