Crossing decorative-leaved and edible-root sweet potatoes

[Diane Whitehead]

I just read this on the Royal Horticultural Society website:

Pat Fitzgerald, founder of Fitzgerald Nurseries based Kilkenny in Ireland.

“I first had the idea for the Treasure Island series during a visit to the USA in 2013,”  “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'  has purple-veined leaves with purple-skinned, orange-fleshed tubers. More are on the way. And the leaves are edible too!

You can order Treasure Island sweet potatoes from Thompson & Morgan.

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

[Richard Watson]

Sounds very interesting

[reed]

They are just all the same species, Ipomoea batatas. Some of them make big storage roots some don't. Some bloom a lot and some don't. Those traits and pretty much all other traits in the species are quantitative so exist in varying degrees. The bloom and rooting traits are not really related, having one does not preclude the other nor is one an indicator of the other.

In the US I think it is preferred for an "ornamental" type not have make big roots so that it doesn't push itself or other plants out of something like a hanging basket. I personally like those that make both so have selected against stringy roots and selected for flowering. Most of the ornamentals on the market here are bred by the University of North Carolina and patented by one of the big nursery companies that supply the big box stores. I get that they don't want the roots but have often wondered why they don't breed their ornamentals to bloom as in my experience it is easy to do.

Color, leaf shape, internode length and everything else are also widely variable and apparently not related good or bad to each other. I could, without much difficulty breed hundreds of different varieties but I select for nice roots and flowers among other things like flavor and root configuration.

Each new seedling is a genetically unique variety that can only be preserved by cloning. In my experience out of any 100 seedlings at least half will be just as nice as those. I throw them away all the time because I don't have a place or reason to keep hundreds of clones that don't meet my other criteria.

[nathanp]

My understanding of the ornamental varieties, at least within the US, is that they were essentially rebranded clones from the sweet potato program that in the past would have been dropped.  Sweet Potatoes that normally would have been dropped due to low yields, until someone got the idea that maybe they could market some of them that had attractive foliage. 

The Craig Yencho video on youtube about sweet potato breeding mentions this.

[Morris Charbonnier]

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'  has purple-veined leaves with purple-skinned, orange-fleshed tubers. More are on the way. And the leaves are edible too!

I grew these varieties last year, plus 'Manihi' and 'Kaukura' from the same Treasure Island series. 'Tatakoto' is actually one of the best flowering/seed setting varieties I've seen (under Central Europe field conditions) so far...

Recently I noticed a tricolor variety ('Tricolor' by PW) . Even though it's far into ornamentals, I'd love to make some experimental crosses with it. Unfortunately, the variety is out of reach for me:(
Let me know if you're working with it!