Calamus ovoideus

Calamus ovoideus is a spiny, evergreen climbing palm in the Arecaceae family. Its common names include egg-shaped rattan and Rotan Ovoid. It is native to southwestern Sri Lanka. There, it grows in wet lowland and lower mountain forests. It occurs below about 4,920 feet [1,500 metres]. Forest gaps and open sites on well-drained slopes suit it. The plant grows wild and has also seen trial cultivation in Sri Lanka.

This palm forms a clump of stout, unbranched climbing stems. Published size figures vary and do not establish a clear garden range. One source lists a height of about 131 feet [40 metres]. Its detailed account gives stem lengths of 164–230 feet [50–70 metres], or more. These figures describe a large forest climber, not a small tree. The pinnate leaves can reach about 13 feet [4 metres] long. The smooth cane is pale brown, with a pale, firm inner core. Stems measure about 0.10–0.16 feet [0.03–0.05 metres] across.

This species needs warm, moist conditions without frost. Its reported habitat has a mean temperature near 27°C. Rain falls throughout the year, and air moisture stays high. The roots grow best in shade, while stems climb toward light. Fairly open forest sites support good growth. PFAF lists sun or part shade and moist, well-drained soil. It accepts sandy, loamy, or clay soils across a broad pH range. PFAF gives USDA zones 10–12 and describes growth as fast.

The cane provides material for baskets and furniture. Workers split it for weaving and use whole stems for frames. Its weight and strength make it a valued rattan. Local people gather wild stems and sell products made from them. The species is scarce in the wild, according to Useful Tropical Plants. That source also reports illegal harvest from forest reserves. Its clumping form has drawn interest for plantation growing.

People eat the very young, still-folded leaves raw or cooked. PFAF records no medicinal use, and both accounts list no known hazards. That does not establish safety for pets or every plant part. The plant is not self-fertile. Seeds lose viability when dry, so they need moisture before sowing. Germination starts after about two and a half to three and a half months. Young seedlings need shade and ample moisture.