My favourite type of flowers are tulips, but to be honest, I'm not much of a flowery person, and I could thing of a million other things I would rather have as a present.
The only person I would ever buy flowers for his my mum. I've bought her flowers for Mother's Day and on her birthday. I usually get them from the supermarket; instead of going for a particular type of flower, I usually go for the ones that have not opened up yet, because they will probably last longer.
I think that home-grown flowers are gorgeous to give someone, even if just a few are added to a bought bouquet. In my opinion, roses and lavender are really lovely as they smell divine and are very pretty. Home-grown bouquets mightn't look as fancy as the shop-bought kind, but they have a sweet old-fashioned charm and it's fun sharing the things that we grow ourselves, whether they're flowers, fruit or vegies.