There are many reasons why a fig tree is not bearing fruit. When a fig tree is not fruiting, there are a few reasons why. The age of the tree (either too young or too old), too much nitrogen, or too much water are the main reasons for the tree not producing fruit.
When the fig tree has had too much nitrogen, this usually happens when using a fertilizer that is too high in nitrogen. Nitrogen causes the plant to have lush growth in leaves and branches, but very little fruit or no fruit. To remedy this situation, use a lower nitrogen fertilizer or add some phosphorus to the soil to counteract the nitrogen.
If a fig tree is suffering from water stress from either too much or too little water, this can cause the tree to stop producing or not start to produce figs. Water stress will cause the tree to go into survival mode so the tree does not have enough energy to produce fruit. Dry, hot periods that occur before ripening can cause poor fruit quality.
If a fig tree is younger, most of its energy goes to producing leaves and shoots. When the plant becomes mature enough (it may take two or more years), the tree will gradually switch from producing mostly leaves and shoots to producing some fruit.