Allium neapolitanum aka White Garlic

Allium neapolitanum is a perennial bulb from the Mediterranean region. Common names include Naples garlic, white garlic, and flowering onion. It belongs to the onion family, Amaryllidaceae. Wild plants grow in dry grassland and fields. It has spread beyond gardens in California, Alabama, Georgia, and Florida. Some parts of the United States regard it as invasive.

Plants form upright clumps with a moderate growth rate. Garden height ranges from about 0.5–1.6 feet [0.15–0.5 metres]. Clumps spread about 1–2 feet [0.3–0.6 metres]. Seeds and new bulbs help them spread. The flat green leaves grow from the base. They have smooth edges and smell of onion or garlic. Sources give leaf lengths of about 1–1.7 feet [0.3–0.5 metres]. The leaves die back after their short growing season. Green flower stems have slight wings along their sides.

White, star-shaped flowers form umbels above the leaves. Each flower has six parts and yellow anthers. An umbel may hold up to 30 flowers. North Carolina State records bloom in May and June. The RHS places flowering in summer. Bees and butterflies visit the blooms. The flowers also suit cutting for indoor use. Capsules form after flowering and hold the seeds.

Grow this bulb in full sun and fertile, well-drained soil. It accepts acid, neutral, and alkaline soils. Sand, loam, chalk, and well-drained clay can suit it. Moist soil is suitable, but the plant also withstands drought. Wet ground can cause the bulbs to rot. The RHS recommends pots where heavy clay stays wet through winter. It lists UK hardiness as H5. North Carolina State gives USDA zones 7–9. Rock gardens, borders, cottage gardens, and pots suit its form. Deer and rabbits tend to leave it alone. Care needs are low; remove spent stems and dead leaves.

Its spread can make it a weed in gardens. Bulb mites, allium leaf miner, and onion fly may attack it. Possible diseases include onion white rot and onion downy mildew. Sources list leaves, bulbs, bulblets, and flowers as edible. Leaves and bulbs have a garlic-like taste. However, North Carolina State also warns of low-severity poisoning from ingestion. All parts may cause nausea, vomiting, or diarrhea. Its food uses do not mean that eating it is risk-free.