Yes, foliar feeding can be used as a supplemental method to provide nutrients to Plumeria. Foliar feeding involves spraying a diluted liquid fertilizer directly onto the plant’s leaves, allowing the nutrients to be absorbed through the foliage. This method is especially useful during periods of rapid growth or when the plant is experiencing nutrient deficiencies. Foliar feeding should not replace regular root fertilization but can be an additional technique to support the plant’s nutrient needs. Use a balanced liquid fertilizer and avoid spraying during hot, sunny periods to prevent leaf burn.