Super succulent is Chelsea Plant of the Year star

A colourful new hybrid succulent was launched at this autumn’s show

Plant breeders need creativity and patience, but liberal quantities of both can yield unique new plants - and a place on rostrum in the Chelsea Plant of the Year competition.
× Semponium ‘Sienna’Daniel Michael, of Surreal Succulents nursery in west Cornwall, saw that with the popularity of succulents on the rise, hardier varieties were needed. This would enable more gardeners to grow more different varieties across more of the country.
Known for his new varieties of aeonium, for use as patio plants, Daniel wondered if they could be crossed with sempervivums – well known for their tolerance of low winter temperatures. Daniel takes up the story.
“For years we have strived to accomplish this despite many challenges,” he explained. “After three years of failed seed batches, in 2017 we carefully crossed Sempervivum ‘Green Ice’ with Aeonium ‘Ice Warrior’ and the result was the birth of the world’s first × Semponium.
“Images and samples were studied by, Julian Shaw, an RHS Botanist, and it was approved as a genuine hybrid. The diversity in the seed batch was outstanding and each seedling was unique, but one stood out over all the rest. This is now known as × Semponium ‘Sienna.’ With colours so vibrant and a form so majestic, it was unlike anything we have ever seen before.”

Dramatic in both colour and form

This is a fast-growing succulent that branches evenly to develop a beautiful conical shape.Having a larger rosette at the top and ever-expanding layers of smaller rosettes creates a dramatic, sculptural form. In spring the green-eyed rosettes are sienna red, in strong light the colour becomes increasingly electric then darkens in autumn.
× Semponium ‘Sienna’ enjoys full sun, is wind and drought tolerant, and grows well in peat free composts. It has proved hardy to -4°C, but hardiness testing continues.
Daniel has selected five other semponiums from his seedlings; these are currently being propagated and will be introduced in due course.

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