Common Names: Cocoa, Cacao, Chocolate Tree
Scientific Name: Theobroma cacao L.
Family: Malvaceae
Native Range: Tropical Central and South America
Growth Form: Evergreen tropical tree

GPS Location: 17° 42′ 55.96″N 64° 49′ 48.47W

General Description

Theobroma cacao is a small tropical evergreen tree best known as the source of cocoa and chocolate.

One of its most distinctive features is cauliflory—the production of flowers and fruits directly from the trunk and older woody branches rather than only from new shoots. These permanent flowering sites can produce flowers repeatedly over many years.

Phenological Markers

1. Vegetative Rest or Reduced Growth

Cacao is generally evergreen, so it does not normally have a completely leafless dormant period.

What to look for:

• Little or no extension of branch tips
• Mature foliage dominating the canopy
• Few newly emerging leaves
• Older leaves becoming duller or slightly yellow
• Reduced flowering during prolonged dry or stressful conditions
• Limited expansion of young shoots

In St. Croix, reduced growth may correspond more closely with drought stress than with a true seasonal dormancy.

2. New Shoot Flush

Cacao commonly produces new leaves in distinct flushes.

What to look for:

• Soft new shoots extending from branch tips
• Young leaves appearing pale green, bronze, pinkish or reddish
• Leaves hanging downward while still soft
• Rapid elongation of the leaf blade
• Groups of new leaves developing simultaneously
• Gradual stiffening and darkening as leaves mature

Young cacao leaves can look strikingly different from mature foliage and provide an excellent visible marker of active vegetative growth.

3. Leaf Expansion

What to look for:

• Young leaves increasing rapidly in size
• Colour changing from bronze or reddish tones toward green
• Leaf blades becoming flatter and firmer
• Petioles strengthening
• Leaves becoming more horizontal
• Mature glossy green colour developing

4. Flower Cushion Activity

Cacao flowers arise from specialized permanent sites called flower cushions on the trunk and mature branches.

What to look for:

• Small raised or knobby areas on older bark
• Tiny buds forming directly from these cushions
• Several buds developing from the same location
• Repeated flowering from previously used cushions

The flower cushions should not be damaged during pruning because they can continue producing flowers and fruit for years.

5. Flower-Bud Development

What to look for:

• Very small rounded buds appearing directly on the trunk or branches
• Buds increasing from pinhead size
• Individual flower stalks becoming visible
• Buds changing from green toward pale pink, cream or reddish tones
• Several developmental stages present simultaneously on one flower cushion

6. Flowering

Cacao produces numerous small, intricate flowers.

What to look for:

• Small star-like flowers opening directly from the trunk
• Five pale sepals, often pinkish or reddish
• Five narrow petals, usually cream, white or pale yellow
• Tiny flowers suspended on slender stalks
• Flowers appearing in clusters from flower cushions
• Fresh flowers opening while older flowers are already falling

Individual cacao flowers are short-lived. Flowers that are not successfully pollinated commonly fall within a day or two after opening.

7. Pollinator Activity

Cacao flowers are unusual because their principal pollinators are tiny midges, particularly species of Forcipomyia, rather than large bees.

What to look for:

• Very small flies or midges moving among flowers
• Insects crawling inside the complex flower structures
• Activity during humid, shaded conditions
• Repeated visits to flowers on the trunk or lower branches
• Other small insects visiting flowers

Because the principal pollinators are extremely small, photographic enlargement or magnification may be helpful.

8. Flower Abscission

Cacao trees produce far more flowers than mature pods.

What to look for:

• Fresh flowers falling beneath the tree
• Flower stalks drying after unsuccessful pollination
• Large numbers of flowers disappearing without producing fruit
• A small percentage of flowers remaining attached after flowering

Heavy flower drop is normal and should not automatically be interpreted as a health problem.

9. Initial Fruit Set

Successful fertilization becomes visible as the ovary begins to enlarge.

What to look for:

• Tiny green swelling remaining after petals fall
• Young fruit approximately pea-sized
• Fruit retaining a connection to the original flower cushion
• Rapid early enlargement
• Several very small pods forming close together

10. Cherelle Stage

Young cacao fruits are commonly called cherelles.

What to look for:

• Small elongated or oval green fruits
• Increasing definition of longitudinal ribs
• Rapid increase in fruit length
• Several young fruits developing on the trunk simultaneously
• Differences in colour depending upon cultivar—green, reddish, purple or intermediate tones

This is one of the most important stages to record.

11. Cherelle Wilt

Many young cacao fruits naturally stop developing and shrivel. This phenomenon is known as cherelle wilt.

What to look for:

• Young pods ceasing to enlarge
• Colour becoming yellow, brown or dark
• Fruits becoming shrivelled
• Wilted pods remaining attached temporarily
• Eventually drying or falling

Cherelle wilt is a normal physiological process by which the tree regulates the number of fruits it can support.

12. Pod Expansion

Successfully developing pods enlarge substantially.

What to look for:

• Steady increase in pod length and width
• Ribs becoming prominent
• Pod surface becoming smoother or more strongly textured depending upon cultivar
• Fruit becoming heavier and hanging outward from the trunk
• Green or reddish immature coloration remaining fairly stable
• Pod stalk thickening to support increasing weight

13. Seed and Pulp Development

Although not directly visible without opening the fruit, this stage corresponds with continuing external pod enlargement.

External indicators:

• Pod approaching full size
• Fruit becoming firm
• Rate of external growth beginning to slow
• Pod maintaining immature coloration
• No obvious softening

Internally, seeds enlarge while the characteristic white mucilaginous pulp develops around them.

14. Physiological Maturity

Research indicates cacao pods generally reach physiological maturity at approximately 150 days after flowering, with harvesting often occurring somewhat later.

What to look for:

• Pod reaching full size
• Growth largely stopping
• Initial colour change beginning
• Ribs fully developed
• Fruit remaining firmly attached to the trunk or branch

15. Pod Ripening

The colour change varies greatly among cacao varieties.

What to look for:

• Green pods becoming yellow or golden
• Red or purple pods becoming orange, reddish-orange or yellow
• Colour change progressing across most of the pod
• Pod reaching maximum size
• Mature seeds surrounded by white pulp internally

Because cultivar strongly affects pod colour, colour change rather than a particular colour is the more useful phenological marker.

16. Mature Fruit

What to look for:

• Full mature colour
• No further enlargement
• Firm pod wall
• Well-developed longitudinal ribs
• Mature seeds enclosed within white pulp
• Pods persisting directly on trunk and mature branches

Cacao fruit commonly requires about five to six months from fertilization to harvest, although temperature and growing conditions can affect development.

17. Fruit Removal or Natural Loss

In cultivation, mature pods are normally harvested rather than allowed to fall.

What to look for:

• Empty fruit stalks remaining on flower cushions
• Harvest scars
• Overripe pods changing colour further
• Diseased or damaged pods
• Occasional fallen fruit

Care should be taken not to damage the flower cushion when fruit is removed because new flowers may emerge from the same location later.

18. Renewed Flowering

Cacao may simultaneously carry:

• flower buds
• open flowers
• cherelles
• developing pods
• mature pods

This overlapping reproductive cycle is one of its most distinctive phenological characteristics.

In suitable tropical environments, flowering may occur throughout the year, although flowering intensity often rises and falls with environmental conditions.

Suggested Observation Schedule

Observe the tree at least monthly, but during flowering and early pod development, weekly or biweekly observations would provide much more useful information.

Record:

• Date
• Recent rainfall or irrigation
• New leaf flush
• Mature foliage
• Flower cushions active
• Flower buds
• Open flowers
• Pollinator activity
• Fallen flowers
• Initial fruit set
• Number of cherelles
• Cherelle wilt
• Expanding pods
• Colour-changing pods
• Fully mature pods
• Fruit loss or harvest
• Evidence of disease or insect damage

Suggested Abundance Scale

For flowers and fruit:

0 — Absent
1 — Very few
2 — Occasional
3 — Common
4 — Abundant
5 — Peak activity

For foliage, it may also be useful to record:

N — New flush
E — Expanding
M — Mature foliage
A — Ageing foliage

Probable Phenological Sequence

Vegetative flush → leaf expansion → flower-cushion activity → flower buds → open flowers → pollination → flower drop or initial fruit set → cherelle stage → cherelle wilt or successful pod expansion → mature pod → colour change → ripe cacao pod

Unlike many trees, this sequence does not necessarily occur only once each year.

On a healthy cacao tree, several stages may be occurring at the same time.

Particularly Valuable Garden Observations

For the St. George Village Botanical Garden specimen, I would pay special attention to:

1. Flowering peaks
Does flowering noticeably increase after rainfall?

2. Pollinators
Are tiny midges actually present on the flowers in St. Croix?

3. Fruit-set percentage
How many flower cushions produce cherelles compared with the number of flowers?

4. Cherelle wilt
At approximately what size do unsuccessful fruits stop developing?

5. Pod-development time
Record the date when a newly set fruit is first observed and the date when its colour begins changing.

That last observation could eventually give the Garden its own locally derived figure for:

flower → fruit set → mature cacao pod

rather than relying upon phenological timing recorded elsewhere in the tropics.