Many organic fertilizers can be considered top dressing under the right circumstances.
The process of top dressing is adding a layer of soil and/or fertilizer on top of what you already have in the garden. This is done in an effort to enrich the soil year after year in the garden so that each successive crop is sustainable. It is also done for landscaping reasons, particularly when gardens have top soil layers that are uneven. Even the visual change can help with the quality of the soil if the top dressing material used is rich in nutrients.
Top Dressing Organic Fertilizer
Not all organic fertilizers are suitable top dressing candidates. In order to be suitable, fertilizer products need to be easy to apply liberally and they need to be effective over long periods of time. Blood meal is a good example of a fertilizer that is suitable for top dressing because it fulfills both of these conditions. On the other hand, something like bone meal, which is rich in calcium and not much else, wouldn't be suitable because it lacks the nutrient depth to enrich the top soil. It is much better for use at the root level.