Arabian Lilac

Scientific name: Vitex trifolia

POWO Status: Shrub or Tree

IUCN Red List threat level: Least Concern

GPS Location: 17° 42′ 55.21″ N, 64° 49′ 50.59″ W

Observations:

Phenological Markers – Vitex trifolia

Common Name: Simpleleaf Chastetree, Beach Vitex, Arabian Lilac
Scientific Name: Vitex trifolia L.
Family: Lamiaceae (formerly Verbenaceae)

Leaf Phenology

Leaf Type: Trifoliate (three leaflets), aromatic when crushed
Evergreen/Semi-deciduous: Evergreen in tropical climates; may be semi-deciduous in drier or cooler seasons
Leaf Flush: New leaves emerge year-round, especially after rainfall or pruning
Senescence: Minimal in stable climates; some yellowing or leaf drop during drought stress

Flowering

Inflorescence: Terminal or axillary spikes or panicles, small purplish-blue to lavender flowers
Blooming Period (Tropics): Primarily late summer to fall, but may flower intermittently year-round
Pollinators: Attracts bees and butterflies
Phenological Indicator: Presence of clustered violet flowers at branch tips; flowers open progressively up the spike

Fruiting

Fruit Type: Small, rounded, fleshy drupe that turns black when ripe
Fruit Development: Forms shortly after flowering; mature fruit visible within ~4–6 weeks
Dispersal: Mainly by birds and gravity
Phenological Indicator: Visible small green-to-black drupes near or following flowering spikes

Suggested Photo Angles

Full shrub/tree in context (can be sprawling or upright)
Close-up of leaf structure (trifoliate arrangement)
Flowering spike with open blooms
Developing and mature fruits
Leaf flush or seasonal yellowing (if observed)

Notes for Monitoring

Flowering may be seasonally synchronized with rainfall, especially after dry periods

Vitex trifolia often grows near coastal habitats, roadsides, and disturbed areas; fast-growing and salt-tolerant

In gardens and arboretums, it may be pruned to shape, which can influence flowering and flush cycles