Even you and I do not sense fragrance the same way, day to day, so that, when we do judge it, we often employ a sight-impaired person hoping that the decrease in one sense might be augmented in the case of the other. Add to that Geraniol , the familiar scent of geranium foliage, Nerol , the essence of magnolias, and, especially in our more modern yellows and oranges, Eugenol , the spicy fragrance which we all know as oil of cloves. Rose fragrance is exuded from glands on the lower petal surfaces, and its amount is limited by both the variety of the rose and by climatic conditions. Sun and warmth are needed for maximum production. Check it out.
Roses are never as fragrant on a cloudy day as on a sunny one.
History tells us of rose petals being strewn over ponds and piled so deep around Roman banquet tables that guests literally waded in them. Two methods came into use, and these all within the last several hundred years. The glass was smeared with rendered fat, or tallow, and the individual rose petals placed on those surfaces one by one, allowed to remain a day or so while the oils were absorbed by the tallow, and then replaced by fresh petals. Meanwhile the tallow was extracted with pure grain alcohol, which separated the fragrant oils from the fat. Sounds like slave labor.