Renanthera Manila
The genus Renanthera currently consists of 22 species and is closely related to Arachnis and Vandopsis with its climbing growth habit in which roots grow along the stem. Some of the species producing the coolest inflorescences in the orchid world filled with small to medium sized flowers in red to orange. The size of the plants varies from approximately 50cm (e.g. monachica) and up to 4 meters (e.g. storiei).
There grows a lot of Renanthera in Singapore, mainly hybrids with Renanthera philippinensis and storiei. These two species are warm growing and want to have lots of light and heat. The most common hybrids in Singapore are Kalsom, Singaporeans, Manila and Fire Coral. In conjunction with the World Expo had a new Renanthera hybrid created and named Renanthera 20th WOC Singapore 2011th I managed to buy two plants of this hybrid that hopefully will give lots of flowers in the coming years.
In this climate Renanthera are often used as border plants where it can grow in full sun along with other plants from the family returned.
Renanthera Kalsom
Cultivation
If you can grow Phalaenopsis and you have a window over which faces the south or southwest, you can try a warm growing Renanthera. A sunny window with a fan that keeps the air in motion it is all it takes to succeed. Then of course it helps to if you have a passion too!
Temperature
Most species and hybrids are warm growing in. Some species such as citrina and vietnamensis are exposed to freezing temperatures in the wild but they will also bloom at higher temperatures. If you can keep the temperature between 15-30 degrees plants from this genus will do well.
Light
In the wild, most species grow very light and sometimes in full sun, or about 4000-5000 fc: 43-53000 lux. Plants from this genus is very adaptable and will usually flower well after a year or so if you can give them the brightest window in winter and a shaded south-west window in summer. During the hottest summer months, plants are preferably grown outdoors. Plants are gradually moved more and more light.
Renanthera 20th WOC Singapore 2011
Watering
During the summer months, from March to September, water the plants daily if they have the roots hanging freely. The other part of the year, every two to three days. If the plants are planted in pots with some form of compost watered them about 2 times a week in summer and about: a once a week in winter. Put a finger into the compost for knowing the roots to dry up between watering’s. The roots of Renanthera and Vanda have to dry out between watering’s, so they feel dry on the surface, otherwise hit them easily by rot.
Fertilizer
The genus is fertilized with the advantage at every watering or once a week throughout the summer. The recommended dose of fertilizer is 1ml per two liters of water at each watering or 1.3 ml per liter of water once a week. During the winter months it is sufficient to fertilize when the sun is shining or every two to three weeks. Fertilizers that can be recommended are 20-20-20 or 15-5-15 CalMag.
Planting
Since most species and hybrids produce large plants it is easiest to grow them in clay pots. As planting material one can use rough bark, charcoal, lava rock or Styrofoam chips. It is important to ensure that the plant is stuck in the pot to prevent it from swaying. The risk is otherwise great that you would damage the roots so that they stop growing with the result that the plant is not growing.
