t sounds like the rose you bought IS dead, and the rootstock that it was grafted on has sprung up in its place. Rose rootstock is cultivated for vigorous growth and hardiness, but not for bloom. That means even if you can prompt the plant to bloom, the blossoms may be mediocre. Experimenting in the garden is always fun, though, so go for it. Mulch your plant and start fertilizing with a high phosphorous fertilizer. Look for a fertilizer with a high middle number--something like 10-30-10 or even 10-60-10. A slow-release granular fertilizer applied to the soil would be best, but you can also occasionally hit it with a water-soluble fertilizer when you water as well.