Tuesday, November 27, 2007
Impatiens chinensis
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 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
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.
Friday, November 09, 2007
Pectecilis susannae
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
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.