Plant Food for Flowering Plants

Flowering plants need the same basic food components---nitrogen, phosphorous and potassium---as all other plants. University of Connecticut's College of Agriculture and Natural Resources advises using a mixture with a higher phosphorous content to promote flower and root development.

Primary Nutrients

• Flowering plants need the three basic nutrients---also called macronutrients---in large amounts. Plant food and fertilizer packaging lists these nutrients as a series of numbers, such as 10-15-10. The numbers correspond to nitrogen, phosphorous and potassium---in that order---and they reflect the amount of each nutrient as a percentage of the total mix, which includes less important ingredients and inert materials.

Secondary and Trace Ingredients

• Fertilizer blends also contain other nutrients that flowering plants need, but in lesser amounts. They include calcium, magnesium and sulfur. Trace ingredients---or micronutrients---needed by plants in very small amounts include iron, boron, zinc, copper, molybdenum, chlorine and manganese.

Flower Power

• Flowering plants can do well with a balanced fertilizer, but some, such as African violets, which are grown primarily for their flowers, benefit from a different blend for optimum bloom. University of Florida IFAS Extension suggests using one-quarter of the normal recommended amount of a water-soluble fertilizer blend of 15-30-15 and applying it each time plants are watered. Excess water should be drained from the bottom of the pots to prevent root rot.