I live in Ireland and did try to grow from seeds, but they all died one by one in various stages of growth. Help... there is no garden center near me that can help.
Licorice plant, Helichrysum petiolare, is easier to start from root cuttings than seeds. Try an internet search using the botanical name. I noticed that this plant is also called silver-bush Everlasting Flower and white licorice making finding the correct plant confusing. Good luck.
Stalk of plant broke in half. I staked the other stalk. Can I restart the broken stalk?
You can, likely, start the tip of the broken vine as its own plant from cutting. This article will help you to take tip cuttings: https://www.gardeningknowhow.com/ornamental/trees/tgen/how-to-root-cuttings-from-various-shrubs-bushes-and-trees.htm
This article will help with growing these plants: https://www.gardeningknowhow.com/ornamental/vines/licorice-plant/licorice-plants-in-containers.htm
My garden is in Southern CA. My three limelight helichrysum ground cover plants are gorgeous and huge. It is time to fertilize and freshly mulch all of the plants they surround. Should I cut them back severely to expose the ground?
Yes, I would, otherwise they will grow over your other plants. Licorice vine is also used in containers or spilling over edges.