|Why is there a black outline on the edge of my rosebuds ?|
|Black margins on the rose petals can be a fungal disease, but is more likely the result of physical damage to the tissue. Look for earwigs or other insects that feed on flower petals. If they have chewed the edge of the petal, it could turn black as it decays. For a more definitive answer, take a sample to your local cooperative extension office. It's important that the sample is fresh when examined.