Sometimes I just buy them for myself, and when I do that, I buy roses. To me, they are the paragon of flowers. They have a lovely, sweet, fulsome scent. They unfurl in the most exquisite crescendo--like a soprano opening her arms to her audience or a diver taking the form of a swan. The juxtaposition of the velvety softness of the petals and the rigidity of the thorns has always fascinated me as well.
I've started reading Foucault's trilogy. One of the things he points out about Victorian public society is the muting of the expression of desire in the public sphere. I find it interesting that the Victorians often expressed their feelings through muted media. Flowers had standardized meanings so that one could encode a message within a bouquet. (Kate Greenaway's The Language of Flowers is a popular reference for such meanings.)
The rose has long been associated with love--each color with a different aspect or species. White is for purity. Pink is for affection. Yellow is for friendship. And red is for romantic love. But my favorite is the rose whose petals are light at the base and darken to the tips. The meaning of this rose is that of long-lasting love.
And so I advocate, now and then, spending a little money on roses, or the flower of your choice. Buy them for yourself. Send them to a friend. For life is too short not to company with and to share beauty.