The result of a cross between H.niger and H x Sternii.

H x sternii, itself, is a cross between H.argutifolius and H.lividus, one of which is green and 1m high and the other small and reddish in colour

Depending on the quantity of genetic influence  of each parent, (really now three parents), you can get a huge variation from this cross.

Many of the  new named  hybrids produced by Tissue Culture that are currently on the market are H x ericsmithii

Strong growing, mostly 45 cms but flower colour can really vary from green to red. Leaves often marbled to varying degrees.