Orchid Bloom Fertilizer XtraBloom is a fertilizer that we specially designed and engineered to make bigger, healthier flower blooms. It has a low nitrogen content to discourage vegetative growth, but a high phosphorus and potash content to support orchids during the critical blooming period. Beyond helping blooms, it is an easy-to-use water-soluble powder that has broad compatibility with other fertilizers. XtraBloom™ is best used in soil or hydroponics applications.