Alright, here are my suggestions:
Boquet of Roses:
Resources Needed: 100 grams of Roses, 10 grams of string
Tools needed: Scissors
Days Needed: 1
Boquet of Daisies:
Resources Needed: 100 grams of Daisies, 10 grams of string
Tools needed: Scissors
Days Needed: 1
Boquet of Buttercups:
Resources Needed: 100 grams of Buttercups, 10 grams of string
Tools needed: Scissors
Days Needed: 1
Boquet of Tulips:
Resources Needed: 100 grams of Tulips, 10 grams of string
Tools needed: Scissors
Days Needed: 1
Assorted Boquet:
Resources Needed:25 grams of Roses, 25 grams of Daisies, 25 grams of Buttercups, 25 grams of Tulips, 10 grams of string
Tools needed: Scissors
Days Needed: 1.5
I also think that the rot rates should be very high with no possibility of repair. I think the regular boquets should rot completly away within a Cantr year, and the Assorted Boquet in 2 years. This would cause the items to be a novelty, and keep people making more of them to give away or sale. I am sure there would be some florist shops opening up...