Answer: It sounds as though the fruits were not adequately pollinated. Avocado fruit production can be helped with the presence of another avocado variety. Temperature during bloom can also influence fruit set. Optimum fruit set occurs at temperatures between about 65 - 75 F. Cooler or warmer temperatures can result in premature fruit drop. The mature avocado tree typically can produce up to about one million flowers but will only typically set about 100 to 200 fruit per tree. Sometimes they will set fruit but then drop them when they are pea to walnut sized. This is typical. You can minimize fruit drop of good "fertilized" fruit by not stressing the tree with too much or too little water. There is also some indication that overfertilizing with Nitrogen during the early fruit stages can also cause premature fruit drop. Since your tree is still quite young, I wouldn't worry about the fruit drop at this point. Once it matures and becomes established, it should provide a bounty of fruits.
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