I remember my grandmother being really superstitious when it came to flowers. In the same way as she did not want anyone to open an umbrella in her home or place new shoes on the kitchen table. She wasn't willing to take the risk of bad luck.
The Language Of Flowers: a Miscellany, is an interesting book to refer to when you want to find out what certain flowers mean.
For example, hazel is for reconciliation, wisteria is for welcome and ivy is for fidelity.
This unique language was created by the romantic early Victorians who carefully planned every bouquet and posy so as to deliver a desired message.
I purchased a basil plant a few days before I read this book and was surprised to find out that it means hate, but it tastes pretty good in my pasta.