Mexican grass tree (Dasylirion longissimum) forms a striking hemispherical rosette 1–1.5 m of extremely narrow, bluish steel needles, creating a fountain effect. In time, a short trunk develops. Drought‑, heat‑ and deer‑resistant, it excels in full sun, gravelly soil and containers, hardy to about −12 °C if dry. A towering flower spike may appear after many years, attracting pollinators. Water sparingly—too much moisture causes rot.