How to Feed Roses to Get the Biggest, Most Beautiful Blooms

For the most part, roses are fairly tough plants that will grow and bloom without demanding much attention from you. But to enjoy the biggest blooms and healthiest growth, roses do need more feeding than most flowering shrubs. Fortunately, it's easy to provide the nutrients they need, and you can do that organically or with synthetic fertilizer products. The key is to give your roses fertilizer that has the right balance of nutrients and to do so on a regular basis. When you feed them on a consistent schedule, they'll reward you with a garden filled with stunning, fragrant flowers.

The Best Fertilizers for Roses

Like all plants, roses need three primary nutrients: Nitrogen (the "N" on a fertilizer label), phosphorus (P) and potassium (K), plus a number of secondary and trace elements. Trace elements (boron, chlorine, copper, and iron) promote plant cell and root growth. Most garden soils provide some of these nutrients but as the plants grow and use them, they become depleted. That's where you come in; adding nutrients back to the soil helps roses perform their best.

Primary nutrients are available from both organic (derived from plant or animal life) and synthetic or inorganic materials. Fertilizers come in dry, liquid, or foliar spray form. Shop for a product labeled for roses and read the directions for amounts and frequency of application carefully. Keep in mind that more is not better; excessive fertilization can damage plants or make them susceptible to disease and insect attack.

Organic options, such as fish emulsion, manures, compost tea, and alfalfa pellets are good choices and have the benefit of being less likely to overload the soil with unnecessary compounds. Commercial products that contain mixtures of organic nutrients are also available. The nutrient concentration in organic products is generally lower, so more frequent applications are recommended, but these products also feed soil organisms and develop humus (organic material, usually from decomposing leaves or the breakdown of other plants), making the soil healthier for plant growth.

When and How to Fertilize Roses

Most roses need regular feeding throughout the growing season. For newly-planted roses, add plenty of compost to the hole at planting time, and then provide a liquid fertilizer (synthetic or organic) about a month later, after they're established. Start feeding older plants in spring when new growth is about 6 inches long. Most will benefit from a second feeding of liquid fertilizer after the first bloom, and repeat-blooming roses do best with regular feeding every 2-3 weeks until late summer.

If conditions are dry, water your roses before feeding them and then, keep them well hydrated afterwards. This helps the plants absorb nutrients better, and prevent fertilizer burn on roots and leaves. Stop feeding about 8 weeks before your average first frost date to avoid stimulating too much new growth that will be damaged by cold temperatures.