Noob here. I haven't planted any perennials, except a peony. Until this year, with a row of periwinkle that I'm attempting to grow up both sides of a lattice. It's working out pretty awesome. They're maybe 20 inches tall, weaving back and forth through horizontal slats.

I want to keep the party going next year, but I'm unable to find out if periwinkle will continue growing in the new year, or if the whole stem dies and has to grow from scratch. I'm aware this question totally unveils how ignorant I am about flowers. Hahah