Interflora

It's not often we can say this about a merchant, but if you need to know more about Interflora then try them out on Wikipedia! They're that big and they've been around that long (first started in 1920!)

Essentially they are a florist shop service that delivers throughout the United Kingdom and worldwide. They have themed floral displays and presents suitable for birthdays, anniversaries, weddings, birth, and housewarming. Apart from flowers they offer hampers and present sets that can include wine, chocolates, gourmet delicacies and fresh fruit.

As their famous marketing campaign said ... whatever it is, "say it with flowers".