Why are flowers fragrant?

1. The reason for the fragrance of flowers

Some flowers have fragrance, while others do not. This is because fragrant flowers contain aromatic oil, which evaporates through their own metabolism and becomes the fragrance we smell.

2. The difference between floral scents

Because flowers contain different aromatic oils, we can smell different floral scents. For example, the scent of flowers such as roses and jasmine is relatively strong. That's because the aromatic oils in these flowers evaporate to a greater extent, and we can smell them from a long distance away. The scent of osmanthus and tuberose is relatively light because the aromatic oils in their flowers do not evaporate very well, so their scents are relatively light. Some flowers do not contain aromatic oils, such as baby's breath. Its flowers have no smell because they do not contain aromatic oils.

3. Other ways of distributing floral fragrance

Some flowers do not contain aromatic oils, but they still smell fragrant. Why is that? Although the plant does not contain aromatic oils, it produces aromatic oils during its metabolism, so these flowers that do not contain aromatic oils can also emit floral fragrance.

Another possibility is that this type of flower contains glycosides. Glycosides themselves have no fragrance, but after being broken down by enzymes, they will emit a fragrance. Therefore, this type of flower can also have a floral scent. For example, the crabapple flower has a floral scent because it contains glycosides. Not all flowers smell fragrant. Many flowers smell bad, such as the Rafflesia. It relies on emitting a foul smell to attract insects and help it spread pollen.