Why do roses smell sweet?

Question

How do they get the smell? And when do roses stop smelling sweet?

Answer 1

Flowers, including roses, have glands (osmophores) that produce their characteristic fragrances in minute oily droplets. These droplets evaporate slowly releasing the scent to attract pollinators like bees. As the day warms they dissipate faster. By late afternoon of a hot day they may be much less fragrant than in the morning. Once fertilized they stop producing the fragrance.

http://www.theflowerexpert.com/content/g...

Roses have very complex fragrances that vary from musky to lemony depending on the parent species. A single rose can have dozens of components to its particular scent so it is made in very small amounts for as short a time as possible, just until pollination.

Fragrance is generated in part by pigment class molecules that also give flowers their colors. This is why color and fragrance are linked. The breakdown products of certain carotenoid pigments are the key odour-contributing compounds in some roses. It is also found in tea leaves, & many fruit.

http://www.leffingwell.com/caroten.htm

The Kazanlik rose is most studied because it is the commercial source of rose attar. The many hundreds of scent producing molecules include phenylethyl alcohol, citronellol, geraniol and nerol, which occur in different proportions from one rose to another.  Geraniol has a sharper character reminiscent of geranium leaves. Phenylethyl alcohol has a soft character typical of pale Gallica roses and is the main scent in rose water. Citronellol is warm and dominant in some of the Rugosa hybrids.

A list of flowers and their constituent fragrance molecules

http://www.bojensen.net/EssentialOilsEng...

Answer 2

Personally I hate the smell of roses.

Answer 3

Because they have an alcoholic compound " citronellol" which gives it its characteristic smell.

As time progresses this compound gets oxidised in the presence of air and loses it properties.

Answer 4

Because roses were made like them. God decided that,