Have you smelt the leaves of a tulsi plant? It smells sweet. So do many other flowering plants such as roses and jasmines. While some flowers have a very attractive fragrance, some others do not have any smell at all. Some other plants have a repulsive smell too.
Flowers and plants have strong smells in order to attract pollinators. Insects are attracted by their smell. These flowers usually have a sweet fragrance; however, there are flowers that have strong stink too. Little flies come to these flowers that give out the smell of rooting meat.
Not all flowers have a fragrance. Plants that pollinate through the wind do not need colours or smell. The flowers that grow on grasses do not have any smell because they rely primarily on the wind for their pollination. Flowers in light colours such as yellow, pink and white attract moths and butterflies that can see. These flowers usually have a faint smell and not a strong one. Flowers that bees frequent do not have any smell generally. Bees see their colours and are attracted to the flowers.
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