The flower above which looks very similar to
a passion fruit flower is actually the flower of a type of gourd known as donkey puhul here in Sri Lanka. The gourd grows downwards from the center of the flower, not unlike an incandescent light bulb.
You can see such a photo as well as recipes
for making a drink and a white curry from the gourd in my cookery book, Katata Rasata Hanikata Uyamu. Both the drink and the curry are delicious. What’s more, these gourds are not cultivated on a commercial scale using chemical fertilizers. Therefore, they are a good choice for those who are
Unfortunately, these type of gourds are not sold widely in markets; so your best option
is to grow a creeper in your home garden. Once again, all instructions can be found in my cookery book (yes, you read that right). Since seeing is believing I have included photographs of the creeper and gourds growing in my own back garden in Colombo. The one featured above was also photographed along with those by my daughter Deepthi Horagoda.