Community breeding of sweet potato within EU for flowering and seed production

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This comes a bit late for this year, but gotta start sometime. There is still time to put the idea forward and make notes this year to help for the years to come. I have now 3 years tried to get seeds from sweet potatoes without success. Partially that is because of my short season and short period to make pollination, but at same time there is lack of varieties that would flower in the first place. I have heard from several sources that some of the varieties that have not even flowered for me over the last 3 years haven’t done so in more favourable climates either. I still have had some flower quite extensively so it seems like it’s just having a bit of luck.

What I’m now suggesting is gathering people that can and want to contribute in some ways. This could be just just taking advantage of varieties that are available locally that might not be available widely and planting them to see if they flower. Then sharing tubers to those that have collected more flowering varieties to grow together. If someone wants to try getting seeds themselves, I have some varieties that at least flower regularly. Few of them are varieties that aren’t widely available. If someone is still interested to try this year, I suppose it’s still not too late for central and southern EU.

I’ll put here list of varieties that I have that I have tried and whether they have flowered. Then you can add information of the varieties that you have and this way we can make a list of varieties that are avaible within the community.

Flowered, available:

Golden eye (heavy flowering both years I have grown it)
Molokai improved (flowered extensively one year, but not after that. Needs more heat?)
Purple 2 (some flowers)
19008 (flowered better first than second year)
21004 (very few flowers)
19002 (if my memory servers my right, also just few flowers)
Erato white (flowered handful of flowers 1 year out of 5-6. Maybe there has been some single flowe´rs before?)
Erato purple (one year flowered profusely, before none or very little)

No flowering, available:

T-65
Witte van de ecohoeve
Scandinavian purple
Beauregard improved
Orange queen

Might have missed flowers or they might flower in some other climate.

What I have had, but have lost.

Carolina ruby (flowered quite well, but not very productive here)
Marjorke (no flowering and didn’t make tubers in my climate)
One variety that I grew from store bought tubers flowered quite regularly, might have been covington.

I’m getting this year (if post deliveres it :sweat_smile: ) one variety and seeds from @Tanjaeskildsen that for her has flowered and produced seeds. Could be someting to start from, but still would be nice to have as many varieties that, if nothing else, to could contribute pollen and that way increase variance.

For people who live in Belgium or travel there https://www.denoudekastanje.be/ has quite a good selection. Many of the ones that I have have come from there, but right now there aren’t that many that would do well in my climate and cost of shipping is quite high. Transplants themselves aren’t too expensive if someone goes by this spring or coming years.

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Lubera has a flowering variety on offer:

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Yes, this is the also the kind of help I was thinking. I have earlier tried googling for sweet potatoes in different languages, and maybe even came across this site, but don’t remember that if there was any available at the time. It’s a bit like looking for a needle in a haystack. Can you check what it says about delivery to other countries?

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They send potted plants, not tubers. Finland is not listed in the shipping cost overview, but Sweden is.

Belgien € 9,90

Bulgarien € 49,90

Dänemark € 34,90

Frankreich € 9,90

Irland € 19,90

Italien € 19,90

Kroation € 44,90

Luxemburg € 9,90

Monaco € 9,90

Niederlande € 9,90

Polen € 14,99

Portugal € 19,90

Rumänien € 44,90

Schweden € 34,90

Slowakei € 34,90

Slowenien € 19,90

Spanien € 19,90

Tschechische Republik € 19,90

Ungarn € 34,90

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Thank you. Seems a little excessive as is ordering plants in big pots to here. It seems like a place to go for someone in the area that is interested in sweet potatoes. There seem to be quite a number of varieties that I haven’t heard of (unless they are other variety with different name), but whether the others are flowering is another matter. No sign in the pictures, but you never know.

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I just ordered three different ones to check them out. They list the sweet potatoes among their own products. Usually their own products come from their own breeding programs. I will dig for more info.

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I would love to take part in this effort. Sweet potato would be a great companion to my Taro plants, which have successfully overwintered indoors two years in a row.

I used to grow many SP varieties in both Hawaii and in Taiwan. Some were excellent used as leafy greens in soups or sautéed. Adapting this species for colder climates, and for seed production, is something id love to assist with.

Im in zone 7 Poland.

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That’s good to know. Always get little suspicious when variety name is just simple colour. Some of the ones did look like quite different from the varieties that I have seen, which is quite a lot said of sweet potatoes that generally have quite limited range of expression of traits. Interested to hear how it goes for you.

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Great. Do you want me to send you some for this season? At this point slips might be the most certain way. Only problem is that this year I have had aphids in them. Outdoors there will be aphids in any case, but just to give you a heads up. In case you have indoor plants etc.

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Yes, i would gladly accept, and have some spots all ready for them. I know people in much colder climates have successfully overwintered them indoors, too.

Ill send you a message with my mailing info.

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It’s fairly easy to keep them over winter as tubers if you have somewhat suitable temps indoors. Udeal would be 13-16C, but anything above 10C up to 20C is ok. High temperatures will only make them sprout and dry faster so it’s recommended to keep them as close to ideal temps as possible.

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I’m linking up some info/reports on the Lubera breeding program for sweet potato, that has been going on since 2014. It’s a big effort. In case you want to contact their breeder for more info: moritz.koehle@lubera.com

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Thank you. have to look into that sometime. Pictures of the rows where every plant looks different look interesting.

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For me these flower every year:

All the trademarked varieties from treasure island, particularly the red leaved variety

Okinawa purple sweet potato (white skin, purple flesh) this is the most reliable seed producer for me and the mother of most of my seedling varieties. It requires a really long season. Surprisingly it’s the most cold tolerant of all the varieties in my garden. Akways the last one to die from frost and the first one to sprout in spring.

All in the sugarroot series from lubera.com

I have more that flowers but I dont know the names of them.

I have a seedling I call lavender as the skin and flesh is lavender coloured. It produces tubers in less than 4 months and lots of seeds. Unfortunately the tubers had zero dormancy last year, so didn’t store well.
But I have cuttings if anyone needs.

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It seems like @Tanjaeskildsen seed grown did the trick and now I have some seed pods forming. Not many (more than ten, probably less than 20) which might be due to that year has not been very good for sweet potatoes and seed grown were a bit late to flower much. But there are seeds forming also in varieties that I have had for years so it must have been those seed grown that helped. Now I have seed pods in one of the seed grown, 19008 and golden eye. Last 2 being the ones that have done best for me in terms of production and flowering so it’s good if I get seeds from them. There are possibly some in molokai improved. Amounts are still too small to start breeding next year, but at least now I know it’s possible and I know which are the varieties I should concentrate on when I try to up the seed production next year. Hopefully can get to hundreds if not to thousands of seeds. Also I had this year erato white flower for the first time. Not many flowers and not sure if it was the stress (bugs and fluctuating temperatures early in the season) . It would be one variety I’d like to get seeds out of. Also erato purple flowered, but that was only the second or third year for it. It flowered more profusely. Has not been very good tuber producer here, but purples tend to need more heat. Purple 2 also flowered very profusely. Edited those to list of flowering.

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Ok, I have harvested this years sweet potatoes, and from the experiences I have had plus after having a conversation with AI, I think I need to adjust my goals a bit. It seems that sweet potatoes currently aren’t really capable of producing a good (or at least the best possible harvest) and have early flowering in my short season at the same time. This year was fairly cool as sweet potatoes are concerned, but with covers, regular rains and watering some did produce fairly well. Flowering overall was late and the best flowering (from @Tanjaeskildsen seeds) don’t seem to want to make many tubers. Another reliably flowering was much later to flower this year, but made good yield. Summa summarum, I need to make area for flowering were I don’t have as heavy fertilization and cut of watering after the plants get started and area were I water them regularly and look for those that make good yield and sow signs of flowering even in good conditions.

This year seed grown I could roughly categorize to;

Very little yield/no signs of flowering (so eliminated). Not many had just tiny tubers and I could have included also those that made yield of around 0.5kg, but since I didn’t get seeds I might as well try and see how different the results are from slips. Based on AI, they should behave somewhat differently as “old plants” so there is a change that either flowering or yield is improved. If nothing else, it gives more data to make better decicions in the future.

Mediocre to ok yield (0.5-1kg)/first visible flower buds at the time of harvesting. These might be one of the most interesting as there is at least a change that they flower in time with little stress, but might also produce good yields from slips in ideal conditions.

Very little to mediocre yield (up to 0.5kg)/heavy early flowering. These might not be lines that will ever produce good yields, but there is a chance that the can pollinate same way as @Tanjaeskildsen seed grown did. Probably they can produce seeds that have the ability to do all the 3 traits fairly good. 2 of them are from varieties that have been flowering fairly early and had fairly good yield potential so next generations might be quite good. Couple of them were also nicely compact plants (less than meter spread), which I find useful. All 3 early flowering came from different varieties so there is good genetic diversity between them.

Fairly good to heavy yield (1-2,5kg)/no signs of flowering. These are ones that would benefit testing in little longer season to see if they also have potential to flower, especially if the conditions are little stressfull. Maybe they also behave differently when grown from slips and adding little more stressful conditions. Since they didn’t show signs of flowering they might not be the best way forward, but there is a chance that they can produce seeds that have traits that support good flowering without sacrificing too much of the yield. Especially in the longer season

Good thing to note about the yields is that many are purple fleshed or partially purple fleshed, which don’t seem to produce as well in short cool season as varieties with different coloured tubers. So partially yields might be lowered by that. On the other hand, there were also varieties that produced more than I would expect from purples.

Now I could share some tubers if @Jacek @eArthur @Tanjaeskildsen or someone else is interested in testing them out. There aren’t that many tubers on some, some have little too big tubers to waste on slips and some had been eaten by rodents, but there are some that have more and overall there are several extras. It might be possible to send transplants during spring also, but sending tubers now after they have cured would be the easiest way. Let me know if anyone is interested.

One purple/white fleshed. Other purples I only checked from smaller tubers what the colour was, but this had one tuber eaten by rodents so I cut those parts of to see better the inside.

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The best producing was the only seedling from beauregard improved. Darker red skin and white flesh, but otherwise tubers grow like beuaregard. Biggest tuber was 1050g.

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