Answer: The most common reasons for lack of fruit set are plant immaturity, lack of sufficient sunlight and incomplete pollination. Since your tree flowered in the spring, it is getting adequate sunshine and is mature enough to develop fruit. The fact that it set small fruit which were then shed indicates the flowers were not pollinated. Fertilizer won't fix the problem - insect activity in and around the flowers will. If the local bees, flies and wasps ignored the flowers in the spring, it could be weather related or it could simply be that they didn't expect to find your tree and therefore ignored it. Next time it flowers (early winter through early spring), take an artist's paintbrush and visit each opened flower, brushing the pollen around and transferring it to the next opened flower. This will result in complete pollination and fruit should form.
Enjoy the fruits of your labors!
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