Alas, I live in Canada (zone 5b) and dont have one of those neato passive solar greenhouses (yet…)
However, a few years ago i found out that I’m juuuust north of maypop’s native range. Then EFN launched the Hardy Maypop Improvement project and I’ve been dreaming of a passionfruit arbor growing in my little Canadian garden ever since.
This year I finally have enough garden space that I can realistically meaningfully contribute to some plant breeding AND I’m 99% sure I finally managed to overwinter a single maypop plant (including an aboveground stem segment! without protection! …it was a mild winter).
So now I’m scrambling to get my hands on more seeds/plants so I can produce fruit and seeds for further selection. Im wondering whether anyone else here is working on this and has made progress that could give me a jump start.
I’d like to first establish a breeding population reliably hardy to zone 5, then hopefully start selecting for flavour/juiciness etc.
I have ordered another packet of hardy maypop seeds from EFN. However, the germination on those packets is quite erratic and slow, and even with a (MUCH) earlier start the last 2 years, I think my biggest challenge was getting delicate baby plants established enough to survive their first winter. I’d probably need A LOT more than one seed packet to bet on getting even one overwintering maypop from an April start.
I can/will also order maypop seedlings from Richter’s so I can at least enjoy some maypops and get my one overwintered plant to produce seed (they are mostly self sterile), but the Richters plants arent selected from the hardiest strains AFAIK so thats a step backwards.
If i were faced with this problem i’d capitulate and grow a selection of different hardy varieties in the highest thin pots the first year, strictly watering from the bottom and then overwinter them inside. Just for the sake of seed increases.
If you’d have unlimited cash, you were say Elon Musk. Would you buy up all passion fruit seeds to throw at this experiment? I think you’d drive the price up for other growers further s0uth, who then get less of a chance to do their screenings for the hardiest.
I believe it’s a bit of a responsability to get ones own seeds in masses while crossing maximally.
As well i’m interested what the growers say at EFN if you’d write to them and lay out the dilemma you’re facing. It could well be they’ve got surplusses (despite me preaching responsable buying) they want you to screen or know other northern growers to connect with.
We need community, that starts with cmmunicating thoughts and intentions.
That is a pretty interesting point, Hugo. I obviously don’t think buying some seed to increase quantity and genetic diversity is problematic, but I agree that you’re right. There is a responsibility, and it will probably ultimately be more likely to be effective anyway, to build up your own seed and draw from the community where possible.
I have not personally ever tasted maypops/passion fruit, but I am fascinated by them and did order some seed a while ago to hopefully get some of our own started here. (We’re in a much warmer climate than you are.)
This would definitely be a concern for some crops but I dont think im at risk of hogging all the maypop, except perhaps in the very limited context of the handful of other people like me trying to get their hands on the hardiest seed.
My understanding is that in less marginal climates, maypop is considered a weed, self seeding prolifically as well as spreading massive distances through rhizomatious roots. It is not grown commercially for fruit(despite producing edible passionfruit! In temperate climates!) because it doesnt travel or show well - ripe fruit drop to the ground and are brown and wrinkly and pop easily. Also because across most of its range, it is viewed as an annoying weed. Its only current commercial value is as a decorative annual plant around the edge of its hardiness range.
Alas, I am not Elon Musk and money is a factor. I can buy a seed packet and/or a potted maypop plant or two, which should be enough to pollinate the hardy specimen I have. My concern is my F2 would then be highly inbred, and have only one parent with proven hardiness.
Also perhaps worth clarifying, although they do muse about zone extention (and sell seeds from the northernmost edge of the native range) the EFN improvement project is focused on improving flavour and appearance of maypop fruit for future cultivation, and is restricted to growers in zones 6+.
Any other mad scientists trying to breed maypop in zone 5 or colder like me are also just tinkering on their own at this point (and I’d love to meet you <3)
People hate it with a passion hère. If grown against a south facing wall it can be problematic. I’ve eaten my. Neighbors but it didn’t have the taste. Looked great.They never fruited at their bouse until i brought another one into the garden.
I live in zone 6, i’d love to plant cold hardy ones.
I think you’re missing the point i’m trying to make. I’m only encouraging you to grow diverse, as many cold hardy traînéd differing plants that you do overwinter to get them through the first year.
Then plant them out, let them cross freely and mass seed theF1 provides you outside and sélect from those for an F2. Sometimes there’s horizontal inheribility going on.
But if you want to buy a lot of seeds, do it. Not my problem.
Oh, I dont want to buy a bunch of seed. I wouldnt even have a place to plant more than a couple dozen plants.
I bought one packet last week after confirming I got one plant to survive a winter out of the packet I bought 3 years ago. Ideally I would like to start producing some fruit and seed this year for both culinary and breeding experiments, but with only one plant with proven hardiness I have a gene base problem, I think?
I’m also concerned that seeds started now won’t necessarily even make it to flower to pollinate my one hardy plant in time to set mature fruit/seed. That is a problem I could solve by just buying a nursery started maypop plant… but that would be an even more limited and dubiously hardy gene base?
If someone else has already made progress on maypop hardiness and has seeds from overwintered maypops in zone 5, or even an unsheltered 6a or lower, that would be a tremendous boost.
I have a real mixed track record trying to keep marginally hardy plants alive fully indoors over winter, but have considered just burying maypop roots in rubbermaid totes full of dirt and storing them in my enclosed front porch over winter, which is a reasonable approximation of a zone 8 or so. Thats definitely on the list of options for fall
Maypop seeds like many northern adapted plants require cold moist stratification for best germination. I put mine in a damp paper towel in a ziplock bag in the fridge for 90 days. You could also sow in flats in the fall and leave them outdoors for the winter.
I am also trying to grow maypops this year up in NE-US (5b). I haven’t ever grown them, but it was a consolation prize instead of growing passion fruit. I got my seed from EFN. I stratified them inside for a bit, then moved them to being directly seeded when we had a melt off a few weeks ago.
If any of them actually sprout and survive this year, I’ll happily share seed if they fruit.
Two plants with differing genetics should get you off to a decent start. They spread a lot unless they are in containers. And even then they might root at a node resting on the ground.
Returned home after being gone for two months. Hubs has been keeping the garden going. No sign of maypops coming up this year. Disappointing. I imagine I’ll try to seed them later this fall before winter hits so they can overwinter in the ground for the full, stratifying season.
I was able to get a couple maypop plants from a friend in MO that I have at my place in Oklahoma right now, but only one has survived the onslaught of heat and grasshoppers so far. If I can keep it alive, I’ll try to bring it home after my contract down there ends and see if it can adapt to an entirely new climate next year.
They should have sprouted under that first wall on the right where that little board is leaning, but nothing that looks like maypops came up. Got a couple volunteer oak trees and one or two tiny maples though.
I purchased two packages of maypop seed from EFN. I cold-stratified the seeds for 90 days and then started them in soil blocks on a heat mat set to 85F under Sunblaster T5 LEDs. Germination was about 25% successful. I gave two plants to a friend, leaving me ten plants which i have potted on to larger containers. I plant to let them grow on until autumn and then i will plant them in the ground.
Another strategy would be to plant them in ground in their pots.
They will root and run. Then dig the pots up and bring the original plants inside in winter, and see if the runners survive.
Mine grow like crazy and fruit, but the “fruits” are always hollow. Anyone know why?
I’m growing maypop but I’m in zone 7b. We had zero degrees Fahrenheit in january 2024 and the vines came back last year from the roots after that. I got a few fruit and I’m growing seed from fruit I saved. My original one was potted from a nursery and they ran and suckered but those are genetic clones. I’m going to try to forage some wild fruit near me this summer to increase my genetic mix. My maypop vines were discovered by some gulf fritillaries last spring and we got hundreds of cool orange caterpillars and orange butterflies, it was amazing. I cold moist stratified my seed in my fridge, then soaked in orange juice for a half day, then grew them on heat mats under grow lights. I have about 50 percent germination, but I never let the seeds dry after picking fruit last year. I’ve been growing maypop for two years, this year will be my third year. This year is my first time successfully getting them to germinate. The vines grow quickly and flower even starting from small plants even planted in May (they pop out of the ground in May here. thus maypop.) so they will probably still flower in time to cross pollinate with your existing one. I have nine seedlings currently growing indoors that I grew from seed.
I wasn’t planning on working on maypops, but last year I got some seeds from the Serendipity Swap box, and when I was going through my seed vault to pull out seeds to stratify, I decided to add them to the list. Current results: a few more sprouts than I expected based on reports about spotty germination! Out of about 12ish seeds, I got this many seedlings!
@Ascentropic my amgio here has made a lot of progress with Diversify Passionfruits. I think his input would be vaulable here.
I haven’t done enough research on Passiflora, but there are a lot of people working on it & many also working to make it cold hardy! It’s something I’m interested in creating as well!
Idk whether to go with the “Grow it as a annual” or “Grow it as a Perennial that survives winter via roots”, but I’m sure both could help bring it closer to your goals.
I’ll share this Passiflora Phylogenic tree, lots of Subgenera & Sections. Some hybrid Combo will eventually work/adapt to your area, Passiflora incarnata genetics are a must!
For anyone who does want to buy a whole bunch of seeds to experiment with, here are two ideas:
1 packet is very expensive per seed ($11.95 for 15 seeds). 1 ounce is very expensive as a total amount ($150 for 876 seeds). But, happily, you can go for something in between the two extremes, because Sheffields will let you buy a decimal quantity of ounces, pounds, or grams of seeds!
Still really expensive per seed: for instance, 0.1 ounces will give you 88 seeds for $27.45.
Probably a much better deal would be Prairie Moon Nursery. You can buy a packet of 10 seeds for $3.50, or 1/8 of an ounce (about 94 seeds) for $10.
I’ve bought bulk seeds from both websites and found them to be good seeds that arrived quickly and were well-packaged.
Mind you, a significantly better option would be to find somebody who lives in a place where it’s a weed, and ask them to forage a few dozen fruits and save you all the seeds. (Or maybe, if you wanted to be able to select for flavor yourself, you could ask them to mail you all the fruits, and pay them back for the postage.) You’d probably get more genetic diversity that way, and it would definitely be cheaper.
I’m not personally interested in maypops, even though they’d be fine for my zone (7b), but I realllllly want some Grandilla passionfruits (Passiflora ligularis), which is a zone 9b plant, so . . . I definitely understand wanting to push the zone to adapt passionfruit.
Got a couple volunteer oak trees and one or two tiny maples though. 
(Or maybe, if you wanted to be able to select for flavor yourself, you could ask them to mail you all the fruits, and pay them back for the postage.) You’d probably get more genetic diversity that way, and it would definitely be cheaper.