Q.Why Are Some On My Passionfruit Leaves Turning Yellow?
Not all are turning yellow but some do and then they fall off. Additionally, i think where the fruit is supposed to grow is turning yellow-ish as well, i’m not sure though.
Certified GKH Gardening Expert
These can be heavy feeders. Yellowing leaves will be an indication that there aren't enough nutrients to sustain the plant, depending on where the yellowing occurs.
These articles will help you to test your soil for deficiencies and pH swings, as well as care for the plant: