Plumeria plants not entering dormancy on the island of Tahiti or similar tropical locations is primarily due to the region’s consistent year-round climate conditions, which do not provide the environmental cues typically necessary for triggering dormancy in many plants. Here are the key factors contributing to this phenomenon:

1. Temperature

Tahiti and similar tropical regions maintain relatively stable and warm temperatures throughout the year. Plumeria plants require a notable decrease in temperature to signal the arrival of the dormant season, typically found in regions with distinct seasonal changes. The consistent warmth in tropical climates means that plumerias do not experience the temperature drop needed to initiate dormancy.

2. Daylight Hours

The variation in daylight hours is minimal near the equator, where tropical regions like Tahiti are located. In contrast, temperate regions experience significant changes in daylight length across seasons, serving as a crucial cue for many plants to enter dormancy. The consistent day length in Tahiti does not signal to plumeria plants that they need to prepare for a period of rest.

3. Growing Conditions

The optimal growing conditions in tropical climates—abundant sunlight, high humidity, and regular rainfall—support continuous growth cycles in plumeria plants. These conditions are ideal for plumeria, allowing them to grow, flower, and thrive without the need for a dormant phase to conserve energy for unfavorable seasons, as there are essentially no unfavorable seasons in such climates.

Evolutionary Adaptation

Plumeria plants, like many tropical species, have evolved to take full advantage of the consistent growing conditions of their native environments. The absence of dormancy in tropical climates is a natural adaptation that allows these plants to grow and reproduce without interruption, maximizing their lifecycle efficiency in stable conditions.

Conclusion

In essence, plumeria plants do not go dormant on the island of Tahiti because the local climate eliminates the need for a dormancy period. The consistent warmth, stable daylight hours, and ideal growing conditions year-round provide an environment where plumerias can continually grow and bloom without the physiological need to enter a state of dormancy for survival through colder or less favorable seasons. This continuous growth cycle is a testament to the adaptability of plumeria plants to their environment, allowing them to thrive in the tropical conditions of Tahiti and similar locales.