Phenology Walk – Achiote
Achiote (Bixa orellana)
Family: Bixaceae
Origin: Native to the Caribbean and parts of Central America
Garden location: 17°42’58.30″N, 64°49’46.20″W
ArbNet Level II list: No
POWO Status: Tree
IUCN Red List threat level: Least Concern
Region
- Native to tropical Central and South America
- Widely cultivated throughout:
- The Caribbean
- Tropical regions of Africa and Asia
- Thrives in:
- Warm, humid climates
- Low to mid elevations
- Well-suited to conditions in St. Croix (USVI), where it grows readily in cultivated landscapes and gardens.
Phenology Markers
Overview
Achiote (Bixa orellana), also known as Annatto or Lipstick Tree, is a small tropical tree or large shrub valued for its vibrant seed pods, which produce the natural dye annatto. At the Garden, it is an eye-catching species due to its soft pink flowers and striking, spiny red fruit capsules.
Growth Habit
- Small tree / large shrub
- Typically 6–20 feet in height
- Open, somewhat irregular canopy
- Rapid grower under favorable conditions
Leaf Phenology
- Leaves are broad, heart-shaped (cordate) with long petioles
- Generally evergreen in tropical climates
- New leaf flush appears:
- As lighter green, soft, slightly drooping foliage
- Often following rainfall or periods of active growth
- Mature leaves deepen to a darker green and become more rigid
Marker:
Look for contrast between pale new growth and darker mature leaves.
Flowering Phenology
- Produces clusters of soft pink to pale lavender flowers
- Flowers have:
- Five delicate petals
- A dense cluster of prominent stamens (often yellow to pinkish)
- Blooming may occur:
- Intermittently throughout the year
- Often in response to favorable moisture and warmth
- Individual flowers are short-lived, often lasting only a day
Markers:
- Bud formation in tight clusters at branch tips
- Sudden appearance of multiple open blooms
- Petal drop within 24 hours, leaving developing ovary
Fruiting Phenology
- Fruit develops into spiny, heart-shaped capsules
- Capsules transition:
- Green → Red (or reddish-brown when mature)
- When mature, pods:
- Dry and split open
- Reveal numerous bright red seeds
- Seeds are coated in the annatto pigment
Markers:
- Early: small green, textured pods
- Mid-stage: swelling, color shift toward red
- Mature: dry capsule beginning to split
- Late: exposed seeds or empty pods
Seasonal Notes (St. Croix Context)
- Growth and flowering are often tied to rainfall patterns
- More vigorous activity may follow wetter periods
- Can show overlapping stages:
- Flowers, immature fruit, and mature pods present simultaneously
Marker:
Achiote often displays multiple phenological stages at once—an excellent teaching specimen.
Ecological & Cultural Notes
- Seeds historically used for:
- Natural dye (annatto)
- Food coloring and flavoring
- Attracts pollinators, especially bees
- Adds visual interest due to:
- Soft floral display
- Bold fruit coloration
Phenology Tracking Notes (Garden Use)
- Ideal for documenting:
- Rapid transitions from flower → fruit
- Color change in capsules
- Seed exposure timing
- Good candidate for:
- Educational walks (clear visual markers)
- Demonstrating tropical, non-seasonal phenology patterns
Suggested Photo Markers
For your page layout, you might include:
- New leaf flush (light green, soft leaves)
- Flower cluster (fresh bloom)
- Flower detail (stamens prominent)
- Early fruit (green, spiny)
- Mature fruit (red capsule)
- Open pod with seeds visible
