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The world’s first ornamental edible sweet potato

Ornamental sweet potatoes that thrive in our climate and reliably produce tasty tubers – the first of a new breed

We’ve come a long way with sweet potatoes in a short time. From “can we get a crop in our climate?” to growing varieties with ornamental foliage in tubs and baskets – now the two come together in the Treasure Island Series of ornamental edible sweet potatoes.

Ipomoea 'Tatakoto' (Treasure Island Series)These are neat and bushy varieties with attractive foliage that looks good in hanging baskets and other containers. But they also produce fat tubers with a yield and flavour to match the edible varieties which so many of us have been growing in our gardens in recent years.

The whole idea is the brainchild of Pat Fitzgerald, founder of Fitzgerald Nurseries based Kilkenny in Ireland. He told me what he had in mind.

“I first had the idea for the Treasure Island series during a visit to the USA in 2013,” Pat told me. “I saw how tremendously versatile Ipomoea was in containers and in the landscape yet none of the varieties had roots that were suitable for eating.

“I asked sweet potato specialist Professor Don Labonte, Director of the School of Plant, Environmental and Soil Sciences at Louisiana State University, why this was – as I understood they were genetically similar.

“Don told me that bringing the two types together was something that was very possible but had never been considered. We chatted about it and thought it would be a fun project – so the seeds were sown. Thousands of seedlings were grown, trialled in Europe, varieties emerged and finally, in 2018, we settled on what is now the Treasure Island Series.

“The concept Treasure Island came from my fascination with the French Polynesian Islands as a child, watching Mutiny on the Bounty as there were tales of Irishmen on board the Bounty. That, and the idea of the sweet potato roots being the treasure under the colourful foliage brought me to choosing the name.”

Three varieties are available, all named for Polynesian islands. 'Makatea' has chartreuse, heart-shaped foliage and orange-flushed, white fleshed tubers. 'Tahiti' has green foliage and dark purple tubers. 'Tatakoto' (above) has purple-veined leaves with purple-skinned, orange-fleshed tubers. More are on the way. And the leaves are edible too!

You can order a collection of all three Treasure Island sweet potatoes from Thompson & Morgan. Or you can also order the three varieties 'Makatea' and 'Tahiti' and 'Tatakoto' separately.

*Also, take a look at Ipomoea Sunpuma Purple (‘SunTun1’), recently featured here, that combines colourful flowers and foliage.

*Please note, the contents of this blog reflect the views of its author and do not constitute an official endorsement by the RHS.

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