Monday, December 24, 2007

Portulaca - Identification Help?!

This is tiny plant. Flower is about 2 cm across. Unlike other P. grandiflora type or hybrids where the flowers open early in morning, this flower open after noon. It appears to have been introduced into Singapore market from Taiwan.

Sunday, December 23, 2007

Iridescent Begonia

A cover photo got to be good right? Here it goes, Begonia pavonina. An iridescent begonia endemic to the highlands of West Malaysia. Iridescence is caused by refraction of light and it is probably best represented in cultivation by "blue" ferns - Pyrrosia sp or fern-allies - Selaginella sp.
Okay it is not really as exciting, the flash from my camera just manages to get it from the right angle and the former picture captures the full glory. The above picture captures an average plant. To some extend, the amount of iridescence depends on intensity of light on the plant, age of leaves, genetics ...

Saturday, December 15, 2007

Yellow Impatiens

This is probably the most beautiful impatiens species endemic to West Malaysia. I. oncidioides is a well documented species found along riverine forest in the montane zone of the Main Range. It is a lush herb that grows not too far from flowing water along earth banks in dappled shade.
Raymond Morgan mentions in his book Impatiens (Timberpress, 2007), that hybridizers have tried to cross this species with New Guinean species to produce good solid yellow flowers... but their efforts are not rewarded. The yellow genes appear to be recessive.

This species is not threaten on account of numerous seedlings and young plants. It even survived grass cutting activity along the trail. But it will not survive destruction of habitat unless transplanted to a suitable montane riverine valley. M. Henderson described this species being common in Cameroun Highlands and Fraser Hill in his 1960s book Common Malayan Wildflowers, but personally i have not seen it at Fraser Hill.

Other companion herbs include an iridescent "blue" begonia by the name of B. pavonina and gesneriads.

Saturday, December 08, 2007

A Hoya?

This is another shy to flower vine. It took a me long time for me to identify it. This leafless green vine is not a hoya, a dischidia or a cynanchum. I first saw it twining over scrub on limestone cliffs at Raleigh beach, Krabi. The impression then was dodder (Cuscuta sp), a parasitic vine commonly found on mangrove and coastal vegetation. But it is too green and has a milky sap, and that helps me to narrow down to milk-weed family (Asclepiadaceae). Again i found it in Halong Bay, Vietnam... twining over Euphorbia antiquorum and other Dracaena. With luck it was in flower and i'm now able to narrow it down to Sarcostemma brevistigma. Unlike Hoya and dischidia, it would never really find a place in collections for lack of flowers and its vining habit. Well it is bless with robustness and a very wide distribution range from India, Nepal, Myanmar and all the way to Thailand, Vietnam and Southern China and is unlikely to face extinction.

Wednesday, December 05, 2007

Euphorbia or Begonia?

This colorful leafy succulent is popular in any sizeable succulent collection. It is probably the closest begonia look alike for a euphorbia species. Euphorbia francoisii is found in under shade from sandy Alluaudia-Didierea thorn forest of southern Madagascar. It is vegetatively allied to Euphorbia decaryi, E. cap-saintmariensis, E. cylindrifolia and E. ambovombensis from the same area. If the plant is seed-grown, there would be a slight basal swelling known as a caudex. The beautiful white-marbled specks, red-hues and veination on the leaves vary from one clone to another. The leaves are very variable and even on the same plant, it is highly dependent on the intensity and the amount of light. Lower leaves being shielded from strong light maybe deep green with little marbling. Generally speaking, high light intensity encourages more white-marbled specks and brings out red hues.

This clone in the photograph below may be a form of E. francoisii v. crassifcaulis 'rubra' with bigger leaves, strong wavy margins and pink veination.
Under equatorial conditions, i learn the hard way after killing cuttings or part of a specimen that it enjoys some shade and will appreciate heat relief under shade when the mercury hits the 35°C or more. Limpy leaves are signs of heat stress or dryness. Caution...if the leaves do not regain turgidness after watering, it maybe under severe heat stress and should be move to a shadier spot for observation and careful watering!

Sunday, December 02, 2007

Dead Leaf Euphorbia

I have this beautiful pot of Euphorbia decaryi var. spirosticha placed strategically near the door to my house. But beauty lies in the eyes of the beholder; a Chinese New Year visitor once asked, "why're you keeping a rotten pile of dead leaves?" Well... i was too upset to correct her. Wait until she got caustic sap white from this plant on her hands, she would realize that it is far from dead.
Surely, if the visitor had looked closer... she would have seen the fresh green new growth! This cryptic mat forming plant is one of my all time favourite Euphorbia. Even if you start off with a cutting or underground stolon or stem with age it forms a mat with new stems spreading out from the center.
E. decaryi comes from the Didierea-Alluaudia forest in Southern Madagascar. It is one of the few Euphorbias with the distinction of being under CITES Appendix 1*. By definition, it is a very endangered and rare species. However, it proves to be very easy and amendable in cultivation and E. decaryi var spirosticha is probably one of the common succulents propagated for sale in nurseries. The type - E. decaryi v decaryi being less attractive is less common in cultivation.

Both varieties are very easy to raise in Singapore - if they are given good bright light and sheltered from rain. They can grow in any mix provided that mix dries out well in between watering. Strong light brings out the brown hues and shade encourages lush green leaves.

*Appendix 1 includes species threatened with extinction. Trade in specimens of these species is permitted only in exceptional circumstances.

Tuesday, November 27, 2007

Impatiens chinensis

It was a painfully slow 24 hrs ride from Hoi An to Dalat. I left Hoi An in the evening to arrive in Nha Trang around dawn. I caught the bus to Dalat at round 9 am traveling at 50 km/hr through rather degraded pastureland. The bus snaked up to the Dalat plateau after lunch. The montane coolness was revitalizing and refreshing; pine plantation started to appear. From the window, i caught a glimpse of delicate pink flowers near ditches or drainage channels. Unfortunately, the bus was not going to stop... However, i was lucky my guide brought me to a less frequent small waterfall the following day to see the dalat sights. Here i managed to photograph this beautiful Impatiens chinensis in situ. It was then approaching the dry season, there were no mature seed pods to be seen.

Trying to pin a name to this species drawed a blank until 2006 when a Taiwanese nurserymen identified it as I. chinensis. It was said to be common weed of Southern China in marshy areas. A websearch yields couple of photos of this species but the flowers are smaller, less symmetrical and the color is inferior. If you can confirm; or suggest another identification, would like to have your comments.

Tuesday, November 20, 2007

Impatiens from Vietnam

I was at Border's this weekend. Wasn't having any expectation of new interesting plant books on the shelf. Browsing through familiar titles i came across a new title Impatiens by Raymond Morgan (Timberpress). The author covered impatiens from Africa, Masdagascar, Indian sub-continent, Southeast Asia and China. Was very tempted to buy it but after the initial excitement... i realized that most species (with pictures) are quite well known. Christopher Grey-Wilson has devoted a monograph - Impatiens of Africa. So i am encouraged start-off with a few impatiens i saw during my travels around Southeast Asia.

I chanced upon this impatiens at Cat Ba Island, Halong Bay during my Vietnam trip in Nov 2005. This perennial balsam was found growing from peaty humus pockets on razor sharp eroded karst. It grows to around 50-80 cm tall from the base and have very pale pink or white flowers. It has a spindle-shaped basal stem up to the first side-branch. Wild plants of Halong Bay identified this as I. verrucifer. Flora of vietnam gives a distribution to include Ninhbinh, Quangnam and Phanrang on the mainland. Athough the plant is flowering vigorously, there is no developing or mature seed pods. I was not sure if November is the flowering season; maybe it is just opportunistic flowering when water is available. That year was probably an anomaly with typhoon bringing rains later and further north. October till April is normally the cool season and past typhoon season. Other plants that share a similar eco-niche are Euphorbia antiquorum, Sacrostemma sp (milk weed stem-climber), Dracaena cambodiana (Yucca-like), Drynaria sp (fern), Stephania sp (climber with peltate leaves & has a tuber).

Saturday, November 17, 2007

Mystery Crassulaceae

This plant is a real pain to identify but only those in Singapore will have this problem. Let me explain... it appears on sale infrequently, it looks like a Kalanchoe, and like kalanchoe it can be started easily from bits of stem or broken leaves, but nobody has seen the flowers. Being right on the equator, okay to be exact just 1° north of the equator, there's no short days of autumn to trigger flowering.

During my recent trip to China, i spotted a nice pot of flowering kalanchoe... but something is not right. The vegetative parts looked like the kalanchoe i know from Singapore but the flowers are wrong! The flowers showed stronger affinities to Sedum. While trying to read up on Chinese plants which i saw during the trip... i come across a photo of the above in The Garden Plants of China by Peter Valder, Timber Press naming it Sedum spectabilis. Going by a more authoritative reference it is Hylotelephium spectabile per Flora of China vol.8. It is found all the way from Eastern China to Manchuria and Korea.

So much for all the mystery... it is just a non-flowering poor specimen of a highly popular ornamental plant introduced to Europe and N. America.

Friday, November 09, 2007

Pectecilis susannae

This is a very famous orchid. It is found in the monsoon belt of Southeast Asia and into S. China, with a very distinct dry and wet season. The natural habitat is seasonal grasslands, in soil pockets amongst rocks and grass. Rumphius named it after his wife in Flora of Ambon:

in memory of her [Susanna] who when alive, was my first companion and helpmate in looking for herbs and plants, and who was also the first one to show it to me

Currently it is very rare in the wild and equally rare in cultivation. It is rare in cultivation probably because of its very specific growth/dormancy requirements and growers tend to treat it like most other orchids which require year round watering. Like H. lindleyana in the former post, after flowering this species dies down to a tuber resting for couple of months before a new shoot will emerge from the soil. At this point, watering can be resumed. It likes to be grown in sandy clay enriched with high potash & phosphate. The mix must retain moisture and must be well drained. The plant grows vigorously for 3-4 mths before flowering developing a tall stem; the stem should be supported if necessary aovid toppling over resulting in unrecoverable damage to basal stem jointed to the tuber. Watering should be slowly reduce as leaves and flowers dries up to prepare for tuber development and dormancy. Some water should still be given to soften the mix and aid tuber development. Here we go, flowers taken back in Oct this year.

A Perfect Flower

Before i left for a 2 week vacation ago, this orchid was budding and sending out a long inflorescence. It is the largest inflorescence that it ever had. Fortunately, i was able to have a friend who's an expert plant babysitter. Under tender loving care; under bright indirect light, careful watering, voila: the flowers of Habenaria lindleyana!

This is a seasonal terrestial orchid from thailand and maybe found in other neighboring countries of indochina. After flowering, the inflorescence and leaves will slowly yellow and die. Meantime watering should be reduced correspondingly. A underground tuber will form in time and if the plant is vigorous, mature and robust... with luck maybe one can get 1 large or 2 tubers. It is important that a dry rest is given; tubers can remain in the potting mix with a dribble of water weekly or twice a month. Normally, the tuber will wake up and develop a growing tip after about 3 months of dormancy not very differerent from onions left on in the kitchen. The active life cycle starts here... regular watering, feeding and pest control etc. Light regular feeding with higher P, K is important to ensure vigorous and active growth. Interestingly, i find that this habenaria enjoys a sandy clay mix which retains moisture.

Monday, October 29, 2007

Stonecrop - Orostachys

This is a surprise for me find to a native succulent in urban China near Shanghai. I first spotted it on a rooftop at Zhujiajiao, a water town just an hour plus from Shanghai. It is growing out between overlapping roof tiles. It is the tall inflorescence that caught my attention. The rooftop mirrors its native ecology - nutrient poor environment, lack of competitive plant species, unhindered exposure to full sun and excellent drainage amongst rocks. The roots anchor steadfast to some dried moss; there is no competitors on this rooftop niche. The following day during excursion to Suzhou, i noted more localities - in LiuYuan (Lingering Garden) and HuQiu (Tiger Hill) on pre-refurbished rooftops.

After doing some research at Shanghai, Fuzhou road bookstores... i manage to narrow it down to Orostachys fimbriatus. It is common plant, use in traditional medicine with poisonous properties... and i quote this from Flora of China 8: 206–209. 2001.

Orostachys fimbriata (Turczaninow) A. Berger in Engler & Prantl, Nat.
Pflanzenfam., ed. 2, 18a: 464. 1930.
瓦松 wa song
Cotyledon fimbriata Turczaninow, Bull. Soc. Imp. Naturalistes Moscou 17: 241. 1844; C. fimbriata var. ramosissima (Maximowicz) Maximowicz; Orostachys fimbriata var. grandiflora F. Z. Li & X. D. Chen; O. fimbriata var. shandongensis F. Z. Li & X. D. Chen; O. jiuhuaensis X. H. Guo & X. L. Liu; O. ramosissima (Maximowicz) V. V. Byalt; Sedum fimbriatum (Turczaninow) Franchet; S. fimbriatum var. ramosissimum (Maximowicz) Fröderström; S. limuloides Praeger; S. ramosissimum (Maximowicz) Franchet; Umbilicus fimbriatus (Turczaninow) Turczaninow; U. ramosissimus Maximowicz.

Rosette leaves linear, short; appendage white, suborbicular, cartilaginous, centrally spinose, margin fimbriate. Stem leaves linear to lanceolate, 1.9–3 × 0.2–0.5 cm, apex spinose. Flowering stem 10–20(–40) cm. Inflorescence racemose or basally branched and conical, dense, 12–25 × 10–20 cm; bracts linear, apex acuminate; pedicels to 1 cm. Sepals oblong, 1–3 mm. Petals red or white, lanceolate elliptic, 5–6 × 1.2–1.5 mm, base connate for ca. 1 mm, apex acuminate. Stamens shorter than or equaling petals; anthers purple. Nectar scales subquadrangular, apex ubemarginate. Follicles oblong, apical beak slender, ca. 1 mm. Seeds numerous, ovoid, minute. Fl. Aug–Sep, fr. Sep–Oct.

Rocks on slopes, house roofs, mossy tree trunks; below 1600 m (to 3500 m in Gansu and Qinghai). Anhui, Gansu, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Zhejiang [Korea, Mongolia, Russia].
This species is used medicinally.

China is actually fairly rich in crassulaceae, with 233 out of 1500 species. With more species in Sedum, Rhodiola, Sinocrassula, Hylotelephium. So... keep your eyes open when you go on holidays.