However, all roses, including Rosa rugosa, need full sun. Roses are heavy feeders, meaning they take a lot of nutrients out of the soil. Consequently, to ensure the health of your roses and that of your soil, it is important to generously enrich the soil around your roses with natural fertilizers. A company called Espoma makes an organic fertilizer called Rose Tone that doesn't contain high salt levels, so it is safe for the environment. Roses enjoy a little extra phosphorus, which promotes flowering.
Bone meal is an excellent natural source of phosphorus.
Potassium will help your roses become more disease resistant. You can easily get potassium to your plants by chopping up a banana peel and placing the bits under the top layer of mulch around your roses. Roses also seem to thrive when given a dose of fish emulsion, perhaps nature's most complete fertilizer. Of course, put a fresh layer of organic mulch around your plants in the spring and late fall. Rugosa rose is an attractive plant.