Pink Shower

Scientific name: Cassia javanica

POWO Status: Tree

IUCN Red List threat level: Least Concern

GPS Location: 17° 42′ 54.73″ N, 64° 49′ 49.41″ W

Medicinal Uses

Cassia javanica (Java Cassia) is used in traditional medicine for its laxative, antidiabetic, antimicrobial, and antioxidant properties, with its leaves, bark, and pods traditionally used for treating constipation, fevers, skin issues, and digestive problems, though scientific studies focus on its potential for diabetes and infections, validating some traditional uses. Key active compounds include flavonoids, anthraquinones, and sterols, supporting its diverse pharmacological activities.

Traditional Medicinal Uses:

Laxative: Ripe pods and seeds are traditionally used as a purgative, similar to Cassia fistula, to treat constipation and colic.
Fever & Pain: Bark and seeds are used as antipyretics (fever reducers) in Thailand, while leaves help with general pain and swelling.
Skin Conditions: Used for skin diseases like leprosy, syphilis, and herpes simplex.
Urinary Disorders: Employed in remedies for urinary issues.
Digestive Aid: Used for general stomach pain and as a carminative (relieves gas).

Scientifically Studied Properties:

Antidiabetic: Leaves and extracts show significant hypoglycemic (blood sugar lowering) effects, supporting its use in diabetes.
Antimicrobial: Effective against various bacteria, including Klebsiella pneumoniae and Proteus mirabilis, and has anti-herpes simplex virus activity.
Antioxidant: Contains compounds that scavenge free radicals, offering protective effects.
Anti-inflammatory: Possesses anti-inflammatory properties.
Hepatoprotective: Extracts show potential in protecting the liver from damage, validating traditional uses for liver ailments.

Active Compounds:

Flavonoids & Glycosides: Contribute to its antidiabetic and antioxidant effects.
Anthraquinones: Known for laxative properties.
Sterols: Also present and contribute to its biological activities.

Observations:

Phenological Markers – Cassia javanica

Common Name: Pink Shower Tree, Apple Blossom Tree, Java Cassia
Scientific Name: Cassia javanica L.
Family: Fabaceae (Caesalpinioideae subfamily)

Leaf Phenology

Leaf Type: Pinnately compound with 6–12 pairs of opposite leaflets; bright green, oblong
Deciduous/Semi-deciduous: Deciduous to semi-deciduous—often drops most or all leaves just before flowering
Leaf Flush: New leaves typically emerge after flowering, often with young reddish or bronze coloration
Senescence: Leaf drop precedes floral display, creating a dramatic “bare-then-bloom” transition

Flowering

Inflorescence: Large, terminal or axillary panicles of pink to rose-colored flowers with yellow stamens
Blooming Period: Late dry season to early rainy season (often spring to early summer in tropical regions)
Pollinators: Bees, butterflies, and possibly sunbirds
Phenological Indicator: Masses of pink blossoms on largely leafless branches—highly conspicuous and seasonal

Fruiting

Fruit Type: Long, cylindrical, woody pod; dark brown to black when mature, up to 60 cm long
Fruit Development: Begins after flowering and ripens over several months
Dispersal: Gravity and possibly animal assistance (pods may remain hanging or drop intact)
Phenological Indicator: Presence of long, dark seed pods hanging from branches, often alongside new foliage

Suggested Photo Angles

Full tree habit during flowering (leafless or nearly so)
Close-up of compound leaves and new leaf flush
Dense pink flower clusters
Developing and mature seed pods
Seasonal contrast between bare, flowering, and flushed states

Notes for Monitoring

Similar in habit to Cassia fistula (Golden Shower Tree), but with pink instead of yellow flowers

Cassia javanica is a spectacular ornamental species known for its dramatic flowering on bare branches, making it easy to photograph and track phenologically

Best time to monitor: Just before and during flowering, when tree transitions from leaf drop to full bloom

Fruit production is less conspicuous but valuable for long-term observation