We love to eat Acca sellowiana formerly Feijoa sellowiana aka pineapple guava.  But growing it has been hit and miss, because in each case, we did not plant it in the correct spot.  My parents had a tree that produced big tasty fruit year after year, apparently in the right spot in their side yard between their house and their neighbor's. 

Our first feijoa was planted by the landscaper in our stone retaining wall 22 years ago.  It is now a big tree.  Some years, it is covered in flowers but they always drop in spite of regular watering.  What I should do is accept that we will never have fruit, and just eat the edible flowers.   The second plant is in our front yard in full sun.  Afternoon sun in super hot Fairfield summers is too much for feijoa.  It has fruited sporadically (and lightly) some years.   However after a pruning 2 years ago, it looks healthy and yet has not produced.  The third bush was planted next to a persimmon tree that is crowding it.  We decided to just let the persimmon flourish in the limited space. 

Finally, the fourth and last plant replaced an ailing evergreen in our backyard. It is against the house, in morning sun and afternoon shade.  I am hoping this one finally has the right conditions for success. This is the third year in ground, and first year its fruited, only on one section.  I am excited to eat the fruit!  Something interesting about pineapple guava is that you don't pick the fruit from the tree. Wait for it to drop, for optimal ripeness and flavor.  Cheers!