While flowers are the reproductive organs of plants, they have certain advantages over both lamb's penises and goat's vaginas:

If a gift is to encourage one to look favourably upon the giver, it must make one feel happy

While a gift can be (and often is) an invitation to or request for the sharing of sex, it is important that the recipient not be revolted by the gift. A bloody piece of flesh is not my idea of a romantic or seductive gift. Something that looks, feels and smells pretty is. 

And no, I don't mean Catherine Zeta-Jones.

So please, don't send me any disembodied goat's-vaginas.
I assume they are unattractive, bloody, smelly (especially after all that time in the post), prickly and clammy. And they certainly won't make me sleep with you.

And anyway.... How on earth would you extract one intact from the goat?