Liquid Fertilizer for Roses

Fertilizer Basics

• Fertilizers are called "complete" if they contain the three nutrients that are most important for plant growth: nitrogen, phosphorus and potassium. The percentages of the nutrients are listed in the order N-P-K on the fertilizer label. For example, the numbers 5-10-5 in a typical dry fertilizer formulation for roses mean the fertilizer contains 5 percent nitrogen, 10 percent phosphorus and 5 percent potassium, according to Herbs2000.com.

Fertilizer for Roses

• Nitrogen stimulates the early spring growth of roses, gives a deep green color to the plant, and promotes stem and leaf growth. Phosphorus, necessary for photosynthesis, promotes root growth and flower production. Potassium regulates metabolism, makes the roses resistant to disease, and gives them hardiness, vigor and good flower color, according to Herbs2000.com.

Definition

• Liquid fertilizers are dry or liquid concentrates of water-soluble inorganic fertilizers, according to Herbs2000.com. They are mixed with water before they are applied. Follow directions on the label for amount to apply, which depends on the formulation.

Considerations

• According to Herbs 2000.com, liquid fertilizers are most appropriate for container roses, which need to be watered often. Frequent watering can make dry fertilizers leach away before they can act. Since liquid fertilizers are water soluble, their ingredients are released immediately. However, they need to be applied frequently, which makes them inconvenient for roses in the garden. Herbs2000.com recommends using liquid fertilizers as a supplement for garden roses.

Application

• Herbs2000.com recommends applying liquid fertilizers as often as every two weeks, using a watering can or sprayer to pour them over the ground or spray them on the foliage. According to Herbs 2000.com, fertilizer applied to foliage is put to use more quickly than fertilizers applied to roots. Do not apply liquid fertilizers to foliage when the temperature is above 90 degrees F, however, because rapid evaporation will make the fertilizers more concentrated and they may burn the plants.