Some sites say this perennial can be grown in zones 5-10, others say zones 6-10. I'm in 6a, and have had this plant at least twice, and both times it did not return the next season. If you're in zone 6, and grow this plant, do you have any helpful hints for me? Thanks!!

Last year I had TWO that came back for me for the first time ever. But they were very late. So I wondered if I had given up on them too soon previously. Fingers crossed this year.

I should say that I love them and will continue to grow as annuals if that is all they will allow me.

In zone 8b . I really like gaura. As long as there is not a severe snow /ice storm in some winters they have reseeded in the garden. A hard freeze will take them out.
Generally they are treated as annuals in zone 6b.
Like some plants in my garden that are tricky to over winter. I will pop them in a wide 18-22" x 8" pot and plant the pot in the ground then lift in winter and keep them in a frost free area until spring. Under a overhang

You inspired me to go and add one to my Bluestone Perennials order! Mine do not look good right now. But perhaps something will emerge from that deep root on at least one!

I had one last a few years here and I found it likes to be a bit on the drier side so maybe a raised spot that drains well.

Siskiyou Pink Gaura …get this one planted as soon as the snow melts.

I am in 6a and have tried a few times with no luck overwintering.

Short answer - no.