Articles
Written by Kawin Jiaranaisakul
Around Khao Lak Merlin Resort, many tree trunks and branches are covered with plants growing above the ground. These plants are called epiphytes. They live on trees for support but do not take food from them. Instead, they depend on rain, humidity, and small amounts of organic debris that collect around their roots.
In Khao Lak, the climate clearly changes between the rainy season and the dry season. During the rainy months, the forest is green and full of growth. Water is plentiful and epiphytes grow new leaves and store energy. When the dry season arrives, rainfall decreases and the air becomes hotter and drier. For plants living high in the canopy without soil, this period can be challenging.
Two common epiphytic ferns in southern Thailand are Platycerium and Drynaria.
Platycerium, often called staghorn fern, has two types of fronds. The round shield fronds press against the tree trunk and help collect fallen leaves and moisture. Over time, this forms a small natural compost layer that holds water. The antler shaped fronds extend outward to capture sunlight. During the dry season, growth slows down, helping the plant conserve water.
Drynaria has creeping rhizomes covered with brown scales. These rhizomes store water and nutrients collected during the rainy season. When conditions become dry, the plant reduces its growth and relies on stored reserves until rain returns.
In both ferns, the dry season is not a time of active growth but a period of survival. The plants pause, conserve energy, and wait for better conditions.
Interestingly, some epiphytes choose the dry season as their time to bloom.
One beautiful example is Dendrobium secundum, known in Thai as the toothbrush orchid. It produces dense clusters of bright pink flowers that resemble the bristles of a toothbrush. Another example is Hoya verticillata, a climbing epiphyte with clusters of star shaped flowers that often have a sweet fragrance.
At first, flowering during a dry period may seem surprising. However, there are simple reasons behind this strategy.
First, there is less rain to damage delicate flowers. Heavy rainfall can wash away pollen or shorten the life of blooms. In dry weather, flowers often last longer.
Second, plants use energy stored during the rainy season. When water was abundant, they built up reserves in stems, roots, or pseudobulbs. During the dry season, growth slows down, so that stored energy can be redirected into producing flowers.
Third, lower humidity can reduce fungal problems. Flowers are sensitive structures, and drier air lowers the risk of rot or infection.
In the forest around Khaolak Merlin, epiphytes follow a clear yearly rhythm. Rainy season means growth and energy storage. Dry season means conservation and, for some species, flowering.
Ferns like Platycerium and Drynaria focus on survival during drought. Orchids such as Dendrobium secundum and climbers like Hoya verticillata may take advantage of the drier months to bloom beautifully against the forest backdrop.
What might look like a harsh season is actually part of a carefully timed life cycle.
These plants are not struggling randomly. They are following a strategy shaped by the predictable climate of southern Thailand.
