Renanthras

Question:

I recently re-bloomed a Renanthera Nancy Chandler and, much to my dismay, the foliage had grown to over 6’ tall! The flowers are lovely but the plant itself is totally impractical. Can anything be done to shrink this orchid? Marc W.

Answer:

Renantheras belong to a family of orchids called Vandas which grow pairs of fan shaped leaves from the center of the plant or ‘crown’, much like Phalaenopsis. Each year, the plant grows taller as more sets of leaves mature on the top. There is no limit as to how tall a Renanthera can grow though many growers use a ‘trick’ to keep the height manageable.

As roots sprout along the cane, the orchid can be ‘chopped’ in two as long as there are roots on both sides of the cut. The two new plants are now half the size and more in keeping with traditional space allotments. There will be some foliar healing time before blooms appear particularly with the lower piece which has to grow a brand new ‘crown’ from the base or side.

Despite their striking beauty – branching spikes with dozens or even hundreds of 1”blood red flowers, it should be noted that Renantheras (and much of the Vanda family) are not well suited to home environments due to their high light requirements – nearly full sun - as well as their daily watering schedule. These orchids do not have pseudo-bulbs and must be watered every day, sometimes twice in the summer! In addition, the potting containers are usually hanging slatted baskets in which long roots dangle to the ground – all of which would be a challenge for even the most creative horticulturalist or interior designer.

Fortunately for the general public, there is a spectacular display of these orchids on display this month in the orchid conservatory of the Lewis Ginter Botanical Garden. Remember to look high in the canopy for the unmistakable scarlet blooms.

 

Question:

I have a miniature Oncidium that is literally blooming in a 1” clay pot. When should I transplant it? Also, the label does not say Oncidium but rather Tolumnia. Which is right? Mary M.

Answer:

It seems most orchid genera have miniature versions – Cattleya Why Not, Phalaenopsis equestris, Dendrobium Betty Nakada, and Paphiopedilum niveum to name a few. Everything about these plants is identical to the standard plants, except the size. Container diameters of 1”, 2”, and 3” are common. Growers must increase the watering somewhat to accommodate the tiny pots.

Re-potting is always done by examining the root systems then choosing the smallest pot that will fit. In most cases, miniatures never grow into large pots.

Botanists are always classifying and re-classifying plant groups and orchids are no exception. The miniature Oncidiums were always known as the ‘equitant type’ until recently. Now they are called Tolumnias. Same delightful plant, just different name.

 

Question:

I was thinking of putting up a shade house for phals and paphs this summer. Any pointers? Lee P.

Answer:

Phalaenopsis and Paphiopedilums are excellent ‘companion’ plants because they like the same low light levels – 1000 to 2000 foot candles – also known as indirect light or shade. They are also compatible in many other cultural requirements but there is one glaring difference. Moth orchids do not like to get ‘rained’ on since they are prone to crown rot. Lady Slippers, on the other hand, seem to thrive on over- head watering.

In order to construct a common building for both genera, there would have to be a uniform shade cloth across the entire facility as well as a waterproof covering (such as plastic sheeting) across the Phals.

Date: 
Saturday, May 1, 2010 - 00:30