Q.yucca
I live on the Ohio River. When I moved here years ago, a cousin’s farm had a lot growing on it. Some of the family in the past had been West and I assumed they brought some back. I now live about four miles from them and have seen several plants. At age 81, I can’t remember exactly where I got mine and it has spread, just as you say with a few plants several feet away. Anyhow, mine bloomed well for several years, and then it quit a few years ago. I asked my county agent who was no help. I read someplace it took a while for a new plant to begin blooming, but once it started it would do so every year! Not mine! It has been several years now. Any advice?
Jon A. Whitfield
Here is a link with more information for you.
https://www.gardeningknowhow.com/ornamental/foliage/yucca/yucca-plant-doesnt-bloom.htm
