Cultivar of Rotala rotundifolia (native to Southeast Asia / southeastern China)
Overview
A background red stem that only earns its name under high light and pressurized CO2; in low light it reverts to green and stretches. Keep nitrates on the lean side and dose iron/traces to hold the blood-red tone, and trim regularly because the tops branch and can shade the lower stems. It arrives emersed or submersed and needs a few weeks to convert its leaves to the true underwater form.
In the wild
'Blood Red' is a selected color form of Rotala rotundifolia, a marsh and paddy-margin stem plant whose wild forms range across Southeast Asia and southeastern China. Standard rotundifolia grows emersed on wet banks with round leaves and turns to narrow submersed leaves underwater. This cultivar was selected for the way it holds deep red rather than the usual pinkish-orange of ordinary rotundifolia.
Good to know
Rotala rotundifolia belongs to the loosestrife family (Lythraceae). 'Blood Red' is one of the reddest of the rotundifolia strains and is noticeably more demanding than the plain green/pink form, needing high light and CO2 to express its color instead of fading to green. The red comes from anthocyanins that build up when the plant is grown lean on nitrogen with strong light, so keeping nitrate low and iron generous intensifies the color.
Did you know
Did you know that despite being sold and grown as a red plant, Rotala Blood Red actually goes greener when you feed it more nitrogen, so growers keep nitrate low on purpose to force the deep red coloration?
High lightBackground11.8 in (30 cm)
High lightBackground15.7 in (40 cm)
High lightBackground19.7 in (50 cm)