March 2017 Plant of the Evening
Sarcochilus dilatatus
This was an exceptional specimen of Sarco. dilatatus rarely seen in monthly benching and shows. The plant was a single growth with 9 leaves mounted on a small tree branch and carried 9 inflorescences with a total of 25 flowers and 20 buds. The flowers are vertical, well presented, averaged 17.5 mm long, widely open and in excellent conditions. The spoon-shaped tepals were green in the centre but becoming a very attractive cerise/ochre at the ends. This coloration indicates that the specimen is a northern form of Sarco. dilatatus, found around Gladstone area of Queensland.
The species is found between south-eastern Queensland and the upper north-east of New South Wales, between the Kroombit Tops (Calliope Range - inland from Gladstone) Queensland and the Richmond River, New South Wales. It is rare in NSW. The preferred habitat appears to be dry, scrubby rainforest and creek beds, noticeably at low to moderate altitudes, up to 400 m altitude and at some distance from the coast. Hoop pines are preferred host of this orchid.
The orchid is a sequential bloomer and in the wild is usually seen with a couple of fully open flowers at a time but the flowering season can last for a couple of months. The floriferousness of the benched plant is exceptional even under culture. According to Bill Dobson, the plant was placed in the shade house together with his Dendrobium tetragonum and due to the unusually hot summer, he had increased the irrigation frequency of the area much more than usual. We are not sure if it was the unusual hot season combined with the irrigation practice which has contributed to the floriferousness.
Sarco. dilatatus has been used in breeding to introduce new colour as well as extend flowering time of Sarcochilus hybrids. It is the parent of two primary hybrids, Sarco. Aussie Dawn (with Sarco. hartmannii) and Sarco. Ozzydil (with Sarco. australis). A few of the well-known and much awarded hybrids include Sarco. First Light, Sarco. Daybreak and Sarco. Galaxy.
The judges were impressed with the plant which was then put up for award judging, both for quality as well as culture awards.
(Photos by Sau-wan Chan)
