Quite honestly, the plant doesn t know the difference between the two. It s only interested in the ions it can absorb through the roots and leaves. But choosing the right fertilizer and applying it correctly has a significant impact on the hardiness and vigor of your plant. For the purpose of discussion, synthetic fertilizers are those that are nitrate-based. Often, they contain ammonium nitrate.
Nitrates are the form of nitrogen used by the plant.
Conversely, organic fertilizers are nitrite-based and must be broken down by microbial activity. Organic fertilizers feed the soil which in turn feeds the plant. Nitrate-based fertilizers can cause serious damage to roses if applied incorrectly or too early in the season. These fertilizers often cause a spurt of tender, young growth - growth that has not had sufficient time to harden before winter's freezing weather is complete. Die-back is often the result.