Allium 'Millenium' is a highly-rated, low-maintenance herbaceous perennial (2018 Perennial Plant of the Year) known for its compact, 15-20 inch, clump-forming habit and abundant mid-to-late summer blooms. It features globe-shaped, rosy-purple flowers that attract pollinators, glossy green foliage, and offers deer/rabbit resistance, drought tolerance, and adaptability in USDA zones 4-8. 
Key Characteristics and Care:
Appearance: Produces dense, 2-inch wide, lavender-purple flowers in July and August, supported by strong, upright stems.
Foliage: Glossy, green, strappy, grass-like leaves that form a neat mound.
Light/Soil: Thrives in full sun to light shade and prefers well-drained soil.
Maintenance: Low maintenance; drought-tolerant once established.
Usage: Excellent for mass planting, borders, rock gardens, and as a cut flower.
Wildlife: Attracts butterflies and bees while resisting deer and rabbits. 
'Millenium' Allium is not a true bulb, but a clump-forming, fibrous-rooted plant, which means it doesn't spread aggressively like some other species. It is an excellent choice for adding texture and late-summer color to the garden.