To choose the best rose fertilizer, examine the needs of both the plant and the gardener. A rose fertilizer is typically categorized in one of two ways, as either organic or synthetic. The gardener may wish to purchase a synthetic fertilizer if he or she wishes to obtain new growth in a specified window of time. Organic fertilizers may be used if overall plant health is desired in a sustainable, long-term form. Many gardeners prefer to use a combination of both methods to achieve their desired results.
A synthetic rose fertilizer will typically be labeled numerically, most commonly as either 10-6-4 or 7-8-5. This indicates to the purchaser the amounts of nitrogen, phosphate, and potash contained, respectively, within the product. Nitrogen provides new growth and new blooms for the plant. Phosphates enrich bloom color and establish strength in the canes. Potash creates new root growth.
The ingredient contained the most in these synthetic fertilizers is soluble nitrates. These nitrates dissolve quickly and are absorbed initially by the plant's root structure. The plant circulates the food and creates new growth and blooms in a relatively short span of time. This is often beneficial for gardeners who wish to showcase their flowers at a particular time, such as for a flower competition or garden show.
Fast, immediate growth on a rose bush is also very attractive to garden pests which feast on the tender new shoots. These include aphids and thrips, both of which use needle-like projections around their mouths to suck nutrients out of the plant. Thus, the use of synthetic materials in fertilizing rose bushes also typically requires a liberal application of pesticides.
Synthetic fertilizers also pose a threat to gardens in that they may strip nutrients away from the soil. The chemical nature of the ingredients found in these fertilizers can cause other important nutrients to wash away from the soil, leaving behind harsh salt deposits. This can deprive nearby plants of the food they need to maintain health, and starve an entire garden plot.
An organic rose fertilizer usually contains the three materials most often needed by rose bushes in a natural form. This type of fertilizer will introduce these nutrients into the soil in which the bush is planted, instead of directly into the root structure. These compounds will release nutrients slowly, allowing for their gradual uptake into the bush over an extended period of time.
Organic fertilizer may be purchased from a garden store or created at home. Organic compost is a common source for rose fertilizer. It may be created by combining leaf clippings, shredded leaves, and kitchen waste, which are all natural sources of nitrogen. This mixture should remain exposed to outdoor elements for one season to allow the ingredients to degrade naturally. Add wood ash for potash and ground bone material for phosphate to complete the fertilizer before applying it to the garden.