The sweet scent of flowers is designed to attract insects; who seek food in the shape of pollen and the fragrant-smelling nectar. This nectar is a solution of sugars produced in little sacs called nectarines at the base of the flower petal.
The insects have a part in the process of fertilization. Almost all plants perpetuate themselves by mean of sexual reproduction, during which a male reproductive cell or sperm fuses with the female reproductive cell or egg. When bees or other insects visit flowers in search of the sweet-smelling nectar, parts of their hairy bodies become dusted with pollen, which contains the male reproductive cells. This rubs off on the flower’s carpels, which contain the egg or ovule.
Insects seem to be strongly attracted by sweet scents. In fact, some flowers, such as the Meadow Sweet, are so highly scented that insects are attracted to them although they have no nectar to offer.