As of April 2015, the highest-rated rose fertilizers on Amazon.com are Jobe's 4102 Rose Outdoor Fertilizer Food Spikes and Miracle-Gro 100022 Rose Plant Food. However, the best fertilizer for a specific job varies depending on the ingredients, cost and effectiveness.Continue Reading
Choosing the best rose fertilizer requires an understanding of the basic nutritional building blocks that the plants need; the three most important nutrients are nitrogen, phosphorus and potassium. Nitrogen promotes green vegetative growth, but too much of it can result in too few blooms. Phosphorus strengthens roots and promotes flower production, while potassium encourages strength and hardiness in plants. Roses also need calcium, magnesium and sulfur. A quality rose fertilizer has all the needed nutrients for roses to thrive.
Reviewers state that the Jobe's fertilizer helped them produce lots of flowers, though some reviewers express concern that the company does not disclose all of the product's ingredients. One advantage Jobe's has over Miracle-Gro is that the fertilizer is in the form of spikes, not granules, which are harder for young plants to process.
While Jobe's and Miracle-Gro are the highest-rated products, their effectiveness depends partially on local soil conditions. Some soils may be too alkaline or have other problems independent of the type of fertilizer used.Learn more about Outdoor Plants & Flowers