Why lumpy orange rind?

Lumpy orange rind is primarily due to the fruit's growth conditions and genetic factors. Irregularities can occur when the orange tree experiences stress from environmental factors like inconsistent watering, nutrient deficiencies, or pest infestations. Additionally, certain orange varieties are naturally more prone to developing a bumpy texture. These lumps can also indicate that the fruit is ripe, as they often develop as the orange matures.