I'm not sure about the lasting qualities of cut meadowsweet, but I'll keep an eye on it and let you know. Keep in mind that my cut arrangements live outdoors so that may skew the results a bit.
The sneezewort is very easy to grow. It's likely taller and floppier than most would prefer but I just let it lean in among the roses. It's easily one of my best filler perennials.
I'll save you some seed.
