[header] How to troubleshoot citrus fruit failure [title] Expect some natural fruit thinning. [step] Citrus fruit that is less than 2.5 cm/1 inch in diameter is often in abundance and the tree cannot carry all these fruits to maturity. Some of these will fall naturally as part of a thinning out. 
[title] Assess the level of water provided to the citrus tree. [substeps] Citrus trees that are not watered adequately have a tendency to drop their fruit prematurely.