Update for the diy bouquet post:
Astonishingly the flowers lasted about 5 days in water!!!
The flowers were weak at that point, (i.e. shake it and it would become a bouquet of stems) but they still looked pretty!
An exception was the lilacs, those did not last more than 2-3 days before they completely shrunk and wilted.
An interesting fact I found is that tulips keep growing after they have been cut, so it was amusing to see the tulips sprouting out of the bouquet!
I have to say I'm pretty happy with those supermarket flowers!