Yes, the gaura plant come back every year in USDA zones 5 through 10. You need good drainage and a bit of winter mulch on the crown. The plant dies down to the root each fall. Fresh shoots push up from the same root the next spring.
I planted three Siskiyou Pink gauras along my sunny path. They came back strong for three full seasons. By year four the plants looked thin and weak. The wands grew shorter and the blooms thinned out.
Gaura is a true gaura perennial but it lives a short life. It joins coreopsis and blanket flower as a short lived perennial. The crowns rarely push strong growth past 4 to 5 seasons. The woody base wears out and the plant fades.
Wisconsin Extension calls gaura hardy in their zone. They warn that individual plants may not be long-lived. USGS bloom data shows flowers from April through November in mild zones. That long bloom run puts heavy stress on the crown each year.
When I first grew gaura, I thought it was failing in year four. I dug up a plant and saw the woody crown had no fresh shoots. Now I plan for a gaura lifespan of about four years per crown. You should plant a fresh one every other spring to keep your colony strong.
The taproot stores energy through the cold months. It fuels the spring flush of new stems. Gaura winter survival rides on soil drainage more than cold air. Wet clay kills more plants than freezing weather ever will. You need to fix your drainage before you plant.
Check your soil by digging a small test hole next to your planting site. Fill it with water and watch how fast it drains away. Your hole should empty in under one hour for happy gaura roots. Slow drainage means you should add grit or move to a raised bed.
Let some of your flower spikes go to seed in late summer. Volunteers will fill the gaps as your parent plants age out. I leave a 6 foot patch at the back of my border alone each fall. You will see fresh seedlings show up by April every spring.
Take 3 inch stem cuttings from your healthy plants in early summer. Do this every two to three years as your backup plan. Root them in damp sand for six weeks. You will have new clones ready to swap in before your old plants fail.
You can keep a healthy stand of gaura going for many years this way. Your plants will not last forever, but your patch will thrive. Mix your seedlings, cuttings, and fresh nursery plants for the best long term results in your garden.
Read the full article: Gaura Plant Growing Guide
