Not only do banana peels contain calcium, magnesium, and sulfur — essential minerals for robust plant growth — but they also help to stave off pests and disease.
To use banana peels as a fertilizer, just chop up the leftover peels, and place them at the base of the hole when planting, allowing nutrients to gradually release into the soil.
If your roses are already in the ground, scatter chopped peels on the soil around your mature plants — as they break down, they'll release the nutrients into the soil.