Passion fruit flowering; no fruit!

[Bsawlsville]

Hi all I have a five-year-old passion fruit vine that makes beautiful flowers but instead of fruiting the flowers just fall off. It gets sun all day and the same vine type about 20 feet away produces great amounts of fruit. Thoughts on why the flowers may be falling and not fruiting? I have even tried hand pollinating but to no avail. I water both the same amount and the soil type is the same

thanks!

 

[Bsawlsville]

 

[Marck]

Hello, welcome to the Forum.

A curious situation; something must be different between the two plants, at least temporarily, but what is it? This does look like the common Purple Passionfruit (Passiflora edulis), but the two plants may not be genetically identical. Do you know if these plants are named cultivars or unnamed seedlings?

You suggest that the two plants' care and culture is identical, but perhaps there is a difference that is not obvious. Check the soil moisture beneath both plants after watering. Perhaps dig a small exploratory hole to look at subsurface conditions. Does one plant stay wetter than the other? Under and overwatering can both affect fruit development.

Fertilizing can also affect a crop. Plants with an over-abundance of fertilizer may not fruit well, but neither will plants with a deficiency. The foliage in the plant mostly looks healthy, though I do see a few yellowing leaves with green veins. This might suggest a metal nutrient deficiency, usually iron.

You mention artificial pollination, I would continue to experiment with that. Timing for successful pollination can be precise, especially for flowers that last only one day, such as those of Passiflora. Also try pollinating between the two plants in both directions, to see if you notice a difference. Even with species that are thought to be bisexual or hermaphroditic, individual plants may still function better as female fruit-bearers or male pollen-producers.

 

[Bsawlsville]

Hi Marck, I really appreciate the feedback and suggestions! This particular vine was actually ground from seeds from my other line so no issue there. I will definitely check out the moisture situation as well as the iron content in the soil. Now that I think of it my vine that does produce fruit is on a hill which probably drains a heck of a lot better than this vine which is on flat ground. I love the idea of cross pollinating as well I will give that a shot. I will let you know how it goes. Have a great day!

 

[Marck]

Sounds great. I'll be curious to hear how it turns out.

 

[RiyaSingh]

Plants with an over-abundance of fertilizer may not fruit well.

 

[Bsawlsville]

This is the fertilizer I use twice a year. Truth be told I’m very ignorant when it comes to fertilizers so not sure if this is what I should be using for this type of fruit

 

[Marck]

This would be considered a low-nitrogen fertilizer. If you are getting sufficient growth on your plants then it is fine. Precise fertilizer formula are only critical in precisely controlled environments, such as optimized commercial greenhouse production. For most gardeners, the important point is that plants receive enough of each nutrient for proper growth. Many plants grown in the ground need no supplemental fertilizer, but crop plants such as your passionfruit may benefit.

The three numbers on the bag, refer to the three macro-nutrients used by plants, Nitrogen (N), Phosphorus (P), and Potassium (K), NPK for short. The K for Potassium, refers to another name for the element, Kalium. There are number of other elemental nutrients that plants use in smaller amounts. These are referred to as micro-nutrients

 

[Bsawlsville]

Hi All, update: I added chelated iron about two weeks ago and flowers are still falling.
I have not cross pollinated with my other vine as I had cut it back a month ago and it is working on getting leafed back up so no flowers right now…

 

[Marck]

Good luck with your efforts. Having your plants be as healthy as possible can only help matters, though I do wonder if there may be a more precise pollination issue at work here, one that might be difficult to pinpoint.

 

[Bsawlsville]

Marck, I’m curious what pollination issues can happen? Can you recommend some good resources for reading up those? Thanks!

 

[Marck]

My thought behind the comment is is mostly that pollinators are not visiting the plant, or that the timing of pollination attempts is wrong. Keep experimenting with artificial pollination, using a paintbrush or even a freshly severed anther.

Cross-pollination is usually not necessary for Passiflora edulis, but there may be an issue with self-fertility in this case. As you told me, your non-fruiting vine is the offspring of your fruiting vine. That makes them similar, but not genetically identical.

Another possibility is the plant has a genetic issue causing sterility, basically some form of deleterious mutation. That may be unlikely but it is a something to consider.

The best resource I can suggest for more in-depth practical expertise is the California Rare Fruit Growers. If you do speak with an expert there and discover the solution, please do post it here on this Forum. I would love to know exactly what is the problem.

California Rare Fruit Growers