Cordyline terminalis is Cordyline fruticosa. The name was changed approximately 7 years ago but many nurseries and horticulturists (including many TV presenters) haven't caught up with the change. Lately there has been a number of Cordylines re-released under differing cultivar names, this is also causing unnecessary confusion.

In regards to Cordyline tubers pushing their way out of the pot. You can cut these from the plant and bury them upright at soil level in the pot. They will form new plants as would cane cuttings but I wouldn't do this until the weather warms up a bit, next month should be fine.

Andrew.

As Andrew says, C. fruticosa is the accepted name, C. terminalis the synonym. The confusion went back to the time of Linnaeus, who named Convallaria fruticosa in 1759 and Asparagus terminalis in 1762, but both names were based on the one plant!

The nomenclatural situation under the present-day genus Cordyline was resolved in some botanical publications as far back as 1919, but confusion has reigned ever since, especially among horticulturalists.

The Flora of Australia (vol. 46, 1986) treatment has the synonymy set out quite clearly. Unfortunately the New RHS Dictionary (1992) got it wrong, but more recent references such as RHS A-Z of Garden Plants, Botanica and Flora all use C. fruticosa