I think I must be one of the last remaining daughters to give the semi-traditional and simple daffodils to my mother today. Local supermarkets and florists have some simple daffodils hidden away behind glitter-dipped chrysanthemums and parrot tulips with eucalyptus and the like. I searched for and found a dwarf variety potted up at the florist and they promise double flowers, though tightly-closed buds are all that can be seen now without even a hint of yellow. I expect they'll be planted out in her garden at some stage too. I don't recall much in the way of Mothering Sunday in Girl's Own (vintage) fiction, though Noel Streatfeild does cover the giving of daffodils and extended family visit in Mothering Sunday when all the mother really wants is a day of peace and quiet. Judging by some of the press attention, it seems that many mothers don't want a fuss made for them, but would like a day for themselves.
Flowers, though, well they are covered in vintage fiction. Lucy Maud Montgomery's heroines gather bouquets of lilies, Elsie Jeanette Oxenham's heroines bestow bunches of flowers on their new friends with varying degrees of patronage and some heroines even grow flowers in their own small gardens. I was always disappointed that P.M. Warner in A Friend for Frances never actually showed us the long-promised bulb fields in Holland as I wanted to see how she'd show the excess of colour and texture. In a more moral vein, the good Chalet girls were actively discouraged from picking wild flowers. I suppose they would have wilted on the return ramble, but it would have been interesting if they'd had a jam jar full of flowers in their flower-curtained cubicles. Elinor M. Brent-Dyer must have preferred floral fabric to the real thing.
I don't recall a career book for girls that dealt with floristry - is there one? Google isn't being of much help this afternoon.