My passion flower (maypop) is a container plant on my porch. This is the first time I have ever had one. . . and it is the most amazing flower ever. I have two issues of concern. First, the flowers bloom and then the next day they are gone. . . not even a shred of evidence they were ever there the next day. Could something be coming along at night and taking them? How long do the flowers usually last once they have bloomed? Second, I noticed that some of the immature blooms never get there and just fall to the ground. Could I be giving too much water? I have it on the porch and it gets sun and shade but not harsh direct sun. Would it prefer the hard afternoon sun?
Passion Flower (Maypop) Issue
Certified GKH Gardening Expert
Several things could be affecting the plant. You may have given the plant too much nitrogen. This causes vigorous growth but little in the way of blooms. You can counter this with adding more phosphorous to the plant. Bone meal is an excellent source of bone meal.
There is a good chance that your bud drop is due to a moisture problem. Passion flower requires plenty of water during the growing season. Low humidity can also cause the buds to dry up and drop.
Your plant could also have some type of pest problem. Tretaing it with neem oil should help with this.