No - it will grow in enriched soil that doesn't dry out too much in summer - what they like is hot, damp summers and dry, chilly winters, but not seriously cold temperatures, which might kill them. Can be grown as a marginal, but I'm not sure how well they actually do if planted as suggested by the aquatic centre, because they'd be wet all year. In the wild in South Africa, they grow along riverbanks, though most of the time, they're not actually immersed in the river.
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They've changed the name to Hesperantha coccinea by the way...

Thanks Bamboo. I have never thought of this as a water plant, but the label still has the old name, pretty picture of a WHITE flower and 'water plant' in about four languages!
the back gives it as zones 1 & 2 which is wet soil to just under the water. Not sure I want to try that, but will see if anyone HAS tried it.

Schizostylis as a name will persist for a long time - they changed the name of Chrysanthemum way back around 1996, but we all still call them Chrysanthemum and they're sold as that too...

Wish the cold weather would kill this. We have bought all the different colours over the years, but now only the red comes up. Seeds itself all over the place from deepest shade to full sun, drought ridden areas.

Ah! Owd, I did wonder if it was 'prolific', so will treat it with care so it doesn't take over the garden. Thanks for the warning.

They are prolific in this garden as we rarely get round to dead heading. Remove the spent flowers and you get no seed, so they do not revert to the standard red.