Allium cyathophorum

Family: Amaryllidaceae

Common name: ONION

Synonym: Allium cyathophorum var. farrerri

Native to: China

Plant

Types: biennial, perennial

Forms: clumping, erect, tufted

Max height: 1.5 feet

Max width: 1 foot

Flower

pink, violet

Leaf

green

Horticulture

Attracts wildlife: adult butterfly, bee, specific butterfly species

Exposure: sun

Propagates by: seed

flowers in summer

Soil type: average

USDA Zones: zone 4 -30 f, zone 5 to -20 f, zone 6 to -10 f, zone 7 to 0 f, zone 8 to +10 f, zone 9 to +20 f

Temp. range: -30 to +30 °F

Water: dry, regular

This is an ornamental onion with a deeply hued violet blossom.

The creative common photo here was taken by Andy King.

These butterflies nectar on Alliums, so may nectar on this one too:
Abaeis nicippe
Aglais urticae
Ascia monuste
Euphydryas chalcedona
Euptoieta claudia
Hesperia sassacus
Hylephila phyleus
Junonia coenia 
Nathalis iole
Panoquina panoquin
Papilio glaucus
Papilio xuthus
Pholisora catullus
Piruna pirus
Poanes melane
Poanes zabulon
Vanessa cardui