Phaius Memoria Pater Agnellus Schneider is flowering

23rd March 2019 I registered Phaius Memoria Pater Agnellus Schneider as a hybrid of Phaius tonkinensis and Phaius phillipinensis.

Memoria Pater Agnellus SchneiderCert

The mother plant was Phaius tonkinensis:

Phaius tonkinensis by Eike Jauch 2

The pollen parent was Phaius philippinensis:

Phaius philippinensis by Eike Jauch

Today I can show you how the flower of the hybrid Phaius Memoria Pater Agnellus Schneider looks like:

Phaius Memoria Pater Agnellus Schneider beschriftet

The hybrid combines the colouration of the Phaius tonkinensis lip with the brownish colour of Phaius philippinensis sepals and petals.

Phaius Memoria Pater Agnellus Schneider 2 beschriftet

Thanks to Gert-Jan for sending me the pics!

 

Gastrochis humblotii var. humblotii

Gastrorchis humblotii var humblotii by Eike Jauch

Gastrochis humblotii var. humblotii is another beautyful malagasy Phaius. The natural biotope of Gastrorchis humblotii var. humblotii are moist forests; some of the trees lose their leaves during the dry season.

Particularly striking is the yellow callus of the lip. It is naked and divided into two. Presumably, the flower is pollinated by bees collecting pollen. It is thought that the yellow callus simulates pollen packets and thus attracts the bees for pollination. Interestingly, the flowers of Gastrochis humblotii var. humblotii do not provide any reward for their pollinators – neither pollen nor nectar. However, they resemble the flowers of Impatiens bisulcata and Coelotryphe synanthera, both in color and in form. Gastrochis humblotii var. humblotii grows together with these two plant species on the mountain Ambre (Montagne d’Ambre) in northern Madagascar in moist, evergreen forests at an altitude of 850 to 1500 meters. So it probably pollinated without having to give something …

Light offer:
Gastrorchis humblotii var. humblotii needs diffused light with illuminances between 15000 and 25000 lux. Direct sunlight should be avoided.


Temperature control:
The average temperature on a summer day is 24 to 25 degrees Celcius in the natural location, at night the temperature drops to 15 to 17 degrees Celcius. This results in a daily temperature fluctuation of 7 to 8 degrees Celcius. In winter, the average daily temperature is 22 degrees Celcius, at night 13 to 15 degrees Celcius. The difference between day and night temperature is 6 to 8 degrees Celcius. Gastrorchis humblotii var. humblotii can cope with temperatures up to 4 degrees Celcius when dry. In the meantime it is clear to me that Gastrorchis humblotii var. humblotii is best cultivated together with Dendrobium nobile hybrids. Although Madagascar is an african island, Gastrorchis humblotii var. humblotii does not like it warm or even hot, especially they it does not like high night temperatures – and even bright sun does not do them any good!


Humidity:
During humid summertime, Gastrorchis humblotii var. humblotii needs 70 to 80% relative humidity.


Repotting:
Best in spring, when the plant resumes its active growth. Gastrorchis are best repotted every year.


Water supply:
During growth Gastrorchis humblotii var. humblotii needs a lot of water. The substrate should be moist but without waterlogging. At the natural site there is a rainy season and a dry season. The dry season initiates the flowering of Gastorchis humblotii var. humblotii. During the rest period watering is reduced and no fertilizer is given. During the resting phase, the light may be brighter than during the growth phase.

Gastrorchis francoisii shows its beauty

It took me many years to get a Gastrorchis francoisii. Most of the plants I bought that were labelled with Gastrorchis francoisii were mislabelled Gastrorchis humblotii. This is a picture of my first true Gastrorchis francoisii flowering. According to Lady Tankeville’s Legacy, this Gastrorchis is considered to be outstanding for the beauty of its largely pale pink blooms that are up to five centimeters across. The side-lobes of the lip are orange, spotted with red at the base.

Gastrorchis francoisii by Eike Jauch

In humid, evergreen forests of central Madagascar, at altitudes of 1200 to 1800 meters, this Gastrorchis thrives in Mandraka Valley. It was first collected by M.E. François, Inspector of Agriculture at the Botanical Garden of Tananarive. In the depths of the internet, I was able to find some cultural information about this beauty, which I would like to put together for you here:

Light:

Gastrorchis francoisii likes illuminations between 18000 and 24000 lux. Since it grows in forests, direct sunshine should be avoided. Here some references: Covered summer day at noon: ~ 20,000 lux, clear winter day at noon: ~ 20,000 lux, covered winter day: ~ 3,500 – 6,000 lux.

Temperature control:

In summer, the temperatures at the natural location during the day fluctuate between 25 to 26 degrees Celcius and at night between 13 to 15 degrees Celcius. Thus, the night reduction should be 13 to 15 degrees. In winter, the average daytime temperatures are between 20 and 23 degrees Celcius, at night between 8 and 11 degrees Celcius. The lowering of the night temperature should therefore be between 12 and 14 degrees Celcius.

Humidity:

The average relative humidity may be 65 to 75 percent.

Repotting:

It is best to repot Gastrorchis francoisii in spring when new shoots show.

Watering:

During growth Gastrorchis francoisii needs plenty of water, but without exposing the roots to waterlogging. At its natural location, Gastrorchis francoisii undergoes a wet growing period and a dry rest period, with little change in humidity.

Fertilization:

If the plant produces new shoots, half-maximum amount of orchid fertilizer, according to the manufacturer’s instructions, may be added weekly.

Rest time:

Gastrorchis francoisii may throw leaves during winter rest period. The plant is hardly poured and fertilization is completely stopped.

Anticipation about Phaius Charlesworthii

Some days ago I was contacted by an australian Phaius enthusiasist to help in identification of a plant she bought as Phaius Charlesworthii. On first sight, the pictures I saw resembled Phaius tankervilleae var. alba. On second sight, there were some morphological signs that pointed clearly towards Phaius Charlesworthii.

Phaius Charlesworthii was registerd by Charlesworth Ltd. in 1900. It is a hybrid of Phaius bernaysii (syn. Phaius tankervilleae var. bernaysii)  and Phaius wallichi (see picture below).

As I do not have this hybrid in my collection, I invited the australian Phaius enthusiasist to write about Phaius Charlesworthii in my blog. In the moment, her Phaius Charlesworthii has two new flower spikes. I cross fingers that they soon bloom. Dear Suzy, thanks in advance for your contribution!

Phaius wallichii 'Jacky' by Eike Jauch

Phaius flavus is an orchid host of Sclerotium rolfsii

In June to July 2002, a fatal rotting disease was observed on Phaius flavus that was grown in the orchid house at the NRCO (National Research Centre for Orchids) in Sikkim, southern Himalaya, India.

Phaius flavus by Eike Jauch

During the inital stage of the fungal infection a basal rot of the pseudobulbs is observed. As the infection spreads leaves turn yellow and finally detach from the pseudobulbs. In the final stage the whole plant turns brown to black and dies.

In 2004 T.K. Bag reported that a fungus was isolated from infected plants and grown on PDA (potato dextrose agar). The isolated fungus produced white septate mycelia. At each septation, clamp connections were observed. Both aerial hyphae and numerous spherical white sclerotia were formed. Upon maturation, the sclerotia turned brown.

The isolated fungus was identified as Sclerotium rolfsii due to morphological and cultural characteristics. Pathogenicity of Sclerotium rolfsii was confirmed under natural conditions on potted Phaius flavus.