Drosera ultramafica
D. ultramafica side view, showing upright rosette nature.
Range: Palawan, Borneo, Sumatra, Sulawesi
Separated in 2011 from Drosera spatulata by Andreas Fleischmann, this unique high-elevation species is found in a currently rather disparate range from high peaks on Palawan in the Philippines, the Kinabalu region of Borneo, the central western coast of Sumatra, and the central highlands of Sulawesi, though further exploration may find it located on many peaks within the archipelago as a whole. It derives its name from its habit of growing exclusively on substrate derived from ultramafic rocks (those high in toxic metals like nickel and chromium), at elevations from 1500-3000 meters in open forests or savannah habitats in regularly moist environments. Plants may grow to 5 cm tall on short stems, with erect to semi-erect (in mature plants) rosettes up to 9 cm across composed of narrow oblong leaves. Petioles are parallel and indumentous abaxially, glabrous adaxially, comprising 1/3-1/2 of the leaf length, and lamina are obovate to oblong and distinct from the petioles in terms of gland presence. Color is typically a muddy olive green with red tentacles to solid deep crimson in strong light. Inflorescences are up to 20 cm tall, mildly indumentous at the base and sparsely glandular in the upper portion, and may sport between 4-15 blooms. The flowers are up to almost 2 cm across, with pure white, distinctly obovate to cuneate (wedge-shaped) petals. This species is quite readily distinguished from its closest relative by the strongly erect stature of new leaves with obovate or elongate ovoid lamina, large flowers, and perhaps most distinctively the presence of red-colored stipules around the base of the leaves (all relatives tend to have colorless or pale white stipules if present).
Cultivation: grow in a 1:1 peat/perlite or sand soil (may appreciate a higher mineral content and better drainage), kept very moist and humid at all times though avoid being sopping wet, with temps of 50-85°F, year round, cooler at night. Do not disturb the plants if possible; movement or repotting can significantly set back growth, and feed regularly for best growth. Sow seeds on soil surface, and grow in strong artificial light to full sun.
Lifespan and reproduction: perennial. Reproduces through seed and occasional root plantlets, and can be grown through leaf or root cuttings.
D. ultramafica top view.
Close-up view; note the red color around the center of the plant in the stipules, especially younger stipules.
The relatively large, white flower of this species.