Rotala macrandra 'Narrow Leaf'

A very narrow-leaved, not entirely stable mutation of the macrandra: it occasionally puts out broad-leaved side shoots. Upright-growing, it produces many side shoots; long stems that have lain down near the surface put out shoots at every node.

It is a little less fussy about conditions than the broad-leaved standard form, but the requirements are much the same: light medium to strong (with too little, the lower stem blackens and dissolves), added CO₂, and carefully controlled macronutrients — nitrate 5–15 mg/l, phosphate 1–2 mg/l. As with most red rotalas, a relatively high phosphate level gives the most compact growth and the strongest red colour. It pales when iron is short and can die without iron fertilising. Trimming: cut off the top and replant it, discard the bottom or leave it — it will put out side shoots. Propagated by tops and side shoots, which root quickly. Difficult, growth fast, CO₂ 20–40 mg/l, temperature 24–28 °C.

Its upright growth makes it more convenient for the background than the similarly textured but less upright Ludwigia arcuata. It is especially good in small layouts — a bright but not overwhelming red accent. Background and midground, a Dutch-style street.

Also under the trade names Rotala 'Magenta' and R. macrandra 'Florida'.