I planted seed from vitifloria polinated with caerulea (Constance Elliot). I only kept one plant from the seedlings. It is 3 years old and has yet to bloom. I have a root sucker that came up from where I had the pot sitting last year. It survived a mild winter in the ground. It is growing strongly but if it does not bloom soon they both are going into compost pile.

Patsy

A very good question.
I don't think anyone knows whether the male or female gives the dominant input re hardiness. It is extremely difficult to tell also as a number of hybrid crosses do not make it clear which is the female. Re vitifolia only one cross of vitifolia x caerulea has ever been named- Passiflora Michael. This cross is notorius for never flowering..so after 3 years scrap it. Also incarnata is a very poor parent for hardy hybrids as its offspring tend to die back to the ground..and not reappear!
Myles

Is that using incarnata as the pollen or ovary parent?

Isn't incense an offspring of incarnata?

~Chills

incarnata is no good either way..for uk-I should have made that clear, and indeed incense does tend not to reappear and is prone to sudden die back. Incarnata is very cold hardy but only if the ground is very dry. Many people do hybrids with it-but for outdoor growing in uk as a species or hybrid it is no good. Also very prone to mildew as are its offspring.

Hi Chills,

'Incense' is a cross of P. incarnata x P. cinncinata. I have one about to start flowering any day now. It did survive outdoors last winter just fine, although it was relatively mild (minimum around 8 degrees F). Most F1 hybrids with incarnata are not very hardy, so you would probably need to backcross to incarnata to select for full hardiness. Usually, interspecific crosses only work one way, so you really don't have much choice as to which species is used as the seed parent.

Concerning the hardiness of incarnata in Europe, I'm not convinced that cold, wet soil is the culprit. I don't dispute the fact that incarnata does not survive well in Europe with wet soils, but it survives here (eastern US) just fine in wet, cold soils. It would seem that there must be some other factor that kills incarnata in Europe in the presence of wet soils. Maybe some pathogen?

Probably not a pathogen. The wrong type of soil I think. The soil here has a lot of clay a couple of feet down and incarnata likes to go down to 3 foot underground to hide over winter- so even if your soil appears wet at the top possibly a lot drier down there. It can't get through the clay is my guess.

I frequently see them wild in areas with heavy clay soils, so I'm not sure that would be an issue. Since they go that deep, maybe its soil temperature related? The mean annual temperature in the native range of incarnata may be significantly higher than in northern Europe. At a depth of 3 feet, our soil will likely be near the mean temperature of 57 degrees F (~14 degrees C) year round. Maybe they can seek refuge from the cold by going deep?