Trying to keep this species alive and make crosses with it. It could be really useful to develop new landraces since its got many resistances, is edible, and can link all 5 domesticated species. The hybrid vigor with domestic species gives 40+ squash per vine. Perennial in warm climates. I’m going to try to keep it growing inside over winter. Hopefully others will also make gene bank requests of this species to work with. Up till now its been used to bring resistance into pepo and bush habit into moschata, if I remember correctly. I think landracer’s could use it it many more interesting ways. So far it I can tell its got really strong heat resistance, more so than the domesticates according to my observation this year. Combine this with the cold resistance of ficifolia, and you can get hosts of interesting multi resistances into landraces.
9 Likes
Cross this with maxima, moschata, or ficifolia and even the F1s male flowers are decently fertile close to 50%. Mixta and pepo can be brought in by crossing to an F1 moschata x lundelliana. All the domestic Cucurbita branched off from this species.
4 Likes
How interesting! I’ve never heard of this species before. Have you had a chance to try the taste of any fruits yet?
Here is a possible source for people who want to grow it next year, assuming they get it back into stock:
The information on that page is highly convincing that it’s another domesticated species, and a great one that’s well worth growing.
I guess there aren’t five domesticated Cucurbita species, after all – there are six! 
1 Like
I did some research on this last night. I learned about its native habitat and its characteristics. I found it interesting to see it likes forest edges, climbs over bushes, hangs over trees and also sprawls over the ground. If I had a swamp, I would buy a few pounds of that seed and gently steward it over a decade or so and let it breed with whatever modern cultivars could handle the swamp: Magic Cushaw. I will likely be acquiring this seed from one source or another.
This appears to offer the highest potential reward yet is the highest mountain to climb.
Emily, I have not tasted it yet. But, even though its sold in markets in Mexico, the references I have found describe it as bitter. One paper in Spanish describes making flour out of the whole fruit. There could be non bitter versions of it out there. There must be hybrids with domestics formed naturally in some places. The Sikil squash shown in the website above–huge props to Cody Cove Farm and the work they’re doing-- is morphologically more like argyrospermia than the 2 lundelliana accessions I’ve grown and what you find in image searches. Therefore, I doubt that one would cross so freely with the other species, but its certainly worth a try.
Austin, it grows naturally also in chinampas. The seed is corky and takes 2-4 weeks soaking in water to germinate. Its classified as mesophytic, like the domestic species. I bet it propagates like crazy in chinampas, but I have it in normal garden conditions. In terms of leaf hardiness to heat this summer, from least to most hardy it went ficifolia, x maximoss, pepo, then lundelliana. It may have more drought tolerance than the domestic species, but it was throughly watered in my garden this year as I only have one plant. I hope you are able to acquire seed. There may be a difference in early vs late flowering. I know someone who grew it in Maryland successfully. The flowers on my plant aren’t open yet, but it may be because it was relatively late in the season getting going. Its definitely not as easy to cultivate as a domestic species, but the freely crossing ability already overcomes the biggest obstacle.
1 Like
I also thought the leaves of the Sikil in their listing look like argryosperma and the fruit appearance does evoke sweet potato cushaw (C. argyrosperma): https://www.seedsavers.org/tennessee-sweet-potato-squash That sweet potato variety almost always is listed as mild tasting flesh, although I have found it listed as being actually sweet a time or two.
I’ve put my email in the alert system when it comes in stock. I’ve also send an email to see if I can get us an idea of whether or not supply is coming.
If I could get some seeds, I would plant them just like any of my Moschatas and give it a few planting spots and see what happens. I would love to cross it with several of my varieties and watch for changes over several years.
Also, I am glad someone else has mentioned the possibility of differences between seed sources. I don’t think this is mentioned enough in general. As soon as seed enters possession, it immediately is subject to change.
The most interesting USDA grin accession I could find is PI 489690.
Oh, cool! So their Sikil variety is probably an interspecies hybrid, which would explain why the fruit tastes good – it’s a cross with a domesticated species, probably selected over many generations to favor domesticated traits like a good flavor.
Sounds like C. lundeliana probably is undomesticated in its pure state, then. Whatever “pure” even means with a species that can cross readily with five others in its genus. 
I received a response from my email. The Sikil variety is expected to become available again next spring.
Austin, I hope you are able to receive some from GRIN ! The Sikil looks interesting too but I think in terms of Occam’s razor, it appears to be C. argyrospermia, with no obvious character’s necessarily pointing to lundelliana. I actually sent that page to a Cucurbita researcher and he said it wasn’t lundelliana, so at this point I don’t see any reason to assume its a hybrid.
Awesome! Research for the win!
If it’s C. argyrospermia, that’s neat, too. It’s the first variety I’ve heard of with that species that has been bred for tastiness as a summer squash. More genetic diversity in favorable traits for a landrace!
Here you can download a paper called “AN INTERSPECIFIC CROSS IN CUCURBITA (C. LUNDELLIANA BAILEY × C. MOSCHATA DUCH”
I haven’t given it a detailed read but some takeaways are 1) F1 is mostly dominant for lundelliana characters 2) the back cross to moschata is mostly like moschata. I can’t wait to try this with ficifolia.
2 Likes