Selaginella martensii

Selaginella martensii is a semi-erect spikemoss from Mexico and Central America that grows into a dense, bushy clump of fine, bright emerald-green foliage closely resembling a miniature cypress or cedar forest when viewed from above. Unlike the creeping S. uncinata, S. martensii has an upright habit reaching up to 30 cm, giving paludariums a genuine three-dimensional forest floor appearance when planted in groups.

Some cultivars, including the popular 'Watsoniana', display attractive silver-tipped branch ends that add further textural interest. It is exceptionally easy to grow in the warm, humid conditions of most paludariums, spreading slowly by stem elongation and rooting at nodes. It prefers a consistently moist, rich substrate and will not tolerate drought or low humidity for extended periods.

Light: Low to medium indirect; 500–2,000 lux; bright light causes bleaching of the delicate foliage. CO2/Humidity: No CO2; maintain humidity above 70%; substrate must remain consistently moist. Fertilisation: Monthly dilute liquid fertiliser at quarter strength; robust grower that does not need heavy feeding. Placement: Plant in groups in rich moisture-retentive substrate in the land zone; trim tops to maintain desired height. Propagation: Stem cuttings placed upright in moist substrate root within 2–3 weeks without any treatment.