Dwarf Citrus Trees can Be grown indoors, they require Bright Light during the winter months indoors. The Sun alone is not enough, Artificial lighting is also required for the Citrus to bloom, or you can just let them go dormant and wait for the summer season to bring Citrus back outdoors in Zone 5a.
Citrus Trees are an acid loving trees like the Hibiscus and Gardenias, besides blooming plant food they also need an acidic plant food. The Citrus friut will not ripen indoors without a heating lamp, but they can bloom.
