- Flowering 15-30-15 Fertilizer is a fast-acting fertilizer with micronutrients increases blooming on flowering plants
- Extra phosphorous encourages maximum numbers of large, long-lasting blooms
- Suitable for indoor and outdoor flowering plants
- Water-soluble concentrated formula
Known as the N-P-K ratio, referring to the nutrients' chemical symbols, those numbers reveal your fertilizer's main ingredients. The first number always indicates nitrogen and its percentage of the formula. The second number reflects the percentage of phosphorus, and the third number represents potassium.
A 15-30-15 fertilizer, for example, contains 15 percent nitrogen and 15 percent potassium – the K at the end of the sequence. Phosphorus comprises 30 percent of the mix.
How Nitrogen Affects Plants
Nitrogen plays an important role in photosynthesis and fuels rapid growth. It helps build energy to keep plants growing strong and stimulates vigorous foliage and stems. Plants with sufficient nitrogen reflect a healthy, deep green color.
Nitrogen-deficient plants may be stunted and show yellowing, called chlorosis, on the leaves. High nitrogen directs the plant's energy into vegetative growth instead of flowering and fruit. Applied late in the year, it encourages vulnerable new growth and delays a plant's entry into winter dormancy. In a 15-30-15 formulation, relatively low nitrogen supports plant energy and minimizes detriments.
What Phosphorus Promotes in Plants
Phosphorus helps plants store the energy that photosynthesis creates. It energizes root growth, which improves a plant's ability to use nutrients. This role is especially important during developmental stages as young roots form. Phosphorus improves plant strength and resilience, and it stimulates prolific flowers and subsequent fruit and seeds.
Phosphorus-deficient plants flower and fruit poorly and show unusually dark green or reddish purple on the leaves. High-phosphorus fertilizers such as 15-30-15 are often referred to as bloom-enhancers. They target increased flowers and fruit.
How Potassium Impacts Plant Growth
Much of potassium's impact happens indirectly. This macronutrient regulates and balances factors controlling plant and root growth. These in turn affect disease and drought resistance, size and quality of fruits and vegetables, cold hardiness and general well-being.
Potassium deficiencies are often reflected in poor overall plant health. Sometimes, deficiency manifests in bronzing and loss of leaves. Potassium keeps plant functions working properly. In a 15-30-15 fertilizer, potassium supports the bloom- and fruit-enhancing qualities of the formulation and helps to strengthen roots.
