OrchidSafari
Orchid Genera whose names begin with R - Renanthera and Restrepia
Moderator: Marilyn Light
May 8, 2002

Copyright Marilyn H. S. Light 2002

[Pre-chat Handout]

RENANTHERA
The genus Renanthera has about 15 species of southeast Asia including Malaysia, Assam, Vietnam and the Philippines. This vandaceous orchid is valued both as a species and for the colorful hybrids produced by breeding selected species with other vandaceous genera. Renanthera plants are monopodial but do produce offsets (keikis) with age. The leaves are stiff, green to reddish green and relatively short as compared to Vandas of comparable size. Flowers are primarily red but some species produce mainly orange yellow blooms that are spotted or barred red purple.

Ren. imshootiana Appendix I is an intermediate grower from Assam and Vietnam. It bears hundreds of cherry red blooms measuring about 2 to 3 inches on long, branched inflorescences.

Warm-growing Ren. bella (Borneo) and Ren. matutina are known from Malaysia Ren. bella has modest numbers of large, 2 to 3 in flowers that are golden yellow, heavily overlaid with red-purple markings while Ren. matutina bears flowers often flushed and marked with fuschia.

Warm-growing Ren. monachica from the Philippines is admired for its compact habit, and sprays of golden yellow blooms covered in red dots.

Renantheras have been extensively hybridized within the genus and within the vandaceous group including Renanthopsis [Rnthps.] (x Phalaenopsis or Paraphalaenopsis), Renantanda [Rntda.] (x Vanda), Renanstylis [Rnst.] x Rhynchostylis. Some famous hybrids include Ren. Brookie Chandler (storei x monachica) and Ren. Nancy Chandler (storei x Brookie Chandler). These are large, 5 to 6 foot tall plants that bear many hundreds of richly colored flowers and are best suited to growing outdoors in the humid tropics or in a warm greenhouse. Raise the plants mounted against the base of an upright post so that they can continue to grow undisturbed for years. Fertilize weekly. Provide 50% shade. Propagate by removing well-rooted offsets or a 12-15 in long top cutting having at least two good roots. Removal of the top of the plant will stimulate the production of at least one new offset, maybe more.

RESTREPIA
Species of the genus Restrepia may be found from Mexico through South America. It is not surprising that amongst the some 25-30 species, there are cool, intermediate and even some warm growers. Flower patterns vary greatly but it is suspected that there may be fewer species than the literature suggests. Restrepia antennifera, known from Columbia and Peru, is extremely variable. The plants are interesting to grow. The stems (ramicauls) are clothed in a series of overlapping and sheathing bracts. The single leaf is rounded, stiff and succulent. New plantlets can emerge from the base of the leaf. When the plantlets form roots, they can be removed or left in place to form an interesting specimen. Flowers are produced singly and seem to open best under humid conditions. The most colorful part is the fused synsepal which may be red to golde, striped or dotted with contrasting colors. Grow Restrepias in moss or in a moss/bark chip mix under humid and buoyant conditions. Provide good air movement. Spray plants with dilute fertilizer solution especially if there are numerous rooted aerial offsets. Restrepias flower year round.

[Discussion begins]

MarilyninOttawa
The genus Renanthera is so named in reference to the kidney-shaped pollinia. The species found in Malaysia include Ren. elongata, Ren. matutina, Ren. histrionica, and the recently described Ren. bella.

The challenge of some Renantheras is their vining habit but thankfully not all species are so inclined. Ren. elongata is a vining plant Plants can be 10's of feet long before flowering! Ren. bella on the other hand is a more compact beauty. It hails from Mount Kinabalu, Sabah, and is pictured on the 30 sen stamp recently issued.

Renanthera imshootiana hails from India to Indochina. It is a cooler grower than the other species but I have had it flower well in the West Indies where night temps can fall below 20C (68F) on occasion.

Flower sizes range from about one inch to about 3 inches. The flowers of Ren. imshootiana are a vibrant red and are produced en masse

To see these plants in bloom just as the sun is setting is to view a landscape on fire. The short, dark leaves disappear in the fading light leaving the flowers floating as it seems in mid air.

Ren. imshootiana is called the Red Vanda in India and like its cousin, Vanda coerulea, the Blue vanda, these were collected almost to the point of extinction. Both species are listed under Appendix I of CITES.

Ren. monachica has flowers measuring up to two inches long. It is much differently colored and grows more modestly. Ren. elongata has rather small flowers but hybridization improves on this. This is Ren. monachica .

John_in_Arcadia_CA
That looks just like my plant of Twin Star (matutina x monachica). It sure took after the monachica.

MarilyninOttawa
I do not have a picture of Ren. matutina to share but here is my best description. Picture monachica but with very narrow segments. Inflorescences are branched and carry 30-40 blooms. Ren. matutina is a species from altitudes of up to 3000 feet in the Cameron Highlands of peninsular Malaysia. It can grow lithophtically. One bit of trivia: the lower sepals are joined.

John_in_Arcadia_CA
That is where the branch came from on my plant. I had 25 flowers with thiner segments that that shown on the monachica. It appears that the color came from the monachica but the size came from tthe matutina. The plant is really quite small 5 inches max across both leaaves and maybe 6 inches tall. Sepals not joined in hybrid

MarilyninOttawa
The 17th WOC was a wonderful opportunity to see some of the many hybrids and intergeneric hybrids made with Renanthera species. I was told that second generation hybrids begin to bring out the color. There is Aranthera Anne Black in two color forms (Ren. coccinea) and my oldtime favorite, Ren. Brookie Chandler (monachica x storiei)

My Ren. monachica, the one you have seen, is a good clone. It is seed-raised which goes to show that good things can come from artificial propagation. These plants grow slowly but flower religiously.

Renantheras in general are small plants in terms of leaf spread. Some simply make up for this short coming by growing like vines. Some very interesting hybrids have been made between Renanthera and Paraphalaenopsis which is registered as Renanthopsis. The plants are compact and the flowers showy. At the WOC, presentations were made on the remarkable hybridization program of the Singapore Botanic Garden where many of the early and old standby hybrids were made. Those of you from warmer climes should be on the lookout for Ren. Kalsom (philippinensis x storiei) which is markedly better in terms of color, substance and plant vigor. The first hybrid was registered in 1931 (Ren. imshootiana x Phal. sanderiana) Renanthopsis Premier.

John_in_Arcadia_CA
Will Renantheras breed with straight phalaenopsis? I have Phal chibae and the Ren Twin Star in bloom now. Maybe I should try them!!

MarilyninOttawa
Yes, but there does not seem to be so much advance in that area.

jim4eq
Wouldn't chibae make the flowers even smaller tho? and wash out the colors. But the spots would match.

MarilyninOttawa
From what I was told by local breeders, the firts generation intergenerics are often disappointing. Second generation hybrids begin to display the hoped for color. I would recommend crossing in both directions.

John_in_Arcadia_CA
Could be but a small flower on a small plant with the hope for red spots MIGHT be interesting. No one will know unless we try - right?

MarilyninOttawa
I thought that we could now move on to the Restrepias. This is a New World genus of pleurothallid species.

The genus Restrepia established in 1816 in honor of Don José Restrepo of Columbia Species include R. hemsleyana (wine red), lansbergii (red spotted), sanguinea (mottled burgundy), muscifera (wine blotched), dodsonii (strawberry pink), and brachypus (wine stripes on gold). Colors are described for the synsepal which is the dominant feature of the flower. Here is Restrepia brachypus .

Restrepia brachypus is rather typical of the genus. The flowers are generally produced singly from the base of a leaf.

Restrepia flowers deserve close examination. The petals and dorsal sepal are narrow and tipped with fleshy and often contrasting colored blobs. The lip is obvious if you look and can be quite distinctive in terms of shape. The two lateral sepals are fused to form a brightly colored or marked synsepal. picture

Restrepia bracypus is an intermediate grower. It grows well for me at 18-20C (65-68F) but constant moisture is an important factor to encourage growth and flowering. My plant has three flowers at present.

Restrepias are intriguing in that you can vegetatively propagate the plant from aerial offsets. The structure bearing the leaf is called a ramicaul. It functions like a vertical stem so it follows that new growths form up above. They also form at the pot level so you can have a lot of material to share if you grow the plants well. picture

Restrepias are quite flexible and can be grown cooler. Simply do the experiment. Watch an actively growing plant as it acclimitizes to the new conditions. Watch the roots. Actively growing roots are a sure sign that your plant likes the conditions. Rather than worrying about temperature, I would be more concerned about keeping the roots moist. These plants really like wet feet. They are mostly cloud forest species and so it follows.

Flower size can vary from about 1/4 inch to more than 2 inches. Restrepia brachypus has flowers measuring almost 2 inches vertically.

Restrepia acutiloba is small but colorful and quite flexible.

pecteilis_in_KY
Use net pots?

MarilyninOttawa
You can probably acquire a plantlet or two from a grower. Try a couple of species. I use sphagnum moss as a mix and keep the pot on the small side. The plants could also be grown in net pots. With net pots, just bear in mind that these plants grow in every direction, from the base, from the top, and from the top of a top. It can become one mess of roots and a challenge to disentangle.

Happy you are inspired to try one of the beauties discussed today.

end