Aerangis orchids should be fertilized with a balanced and diluted fertilizer every two weeks during the growing season (spring and summer) and once a month during the resting period (fall and winter). It is important to dilute the fertilizer to half or quarter strength to avoid burning the roots. Use a fertilizer that is high in nitrogen for improved leaf growth and a fertilizer that is low in nitrogen for improved flower growth. Fertilization should be avoided during drought or severe heat. Always water the orchid thoroughly before fertilizing to prevent fertilizer burn.