Allium cepa ‘Shallot’
(sold as Ambition, Armador, Cuisse de Poulet echalion, Matador)

Family: Amaryllidaceae

Common names: AGGREGATUM GROUP, SHALLOT

Native to: Not Known In The Wild

Plant

Types: annual, biennial

Forms: erect, tufted

Max height: 4 feet

Max width: 1.5 feet

Flower

white/off white

Leaf

green

Horticulture

Attracts wildlife: adult butterfly, bee, specific butterfly species

Seedling days to mature: 90-150

Edible: vegetable

Exposure: sun

Propagates by: seed

flowers in summer

Soil type: average

USDA Zones: 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: -20 to +30 °F

Water: dry, regular

Here is a vetted list of SHALLOT bulbs for the home garden:
Ambition -- AGGREGATUM GROUP
Armador -- AGGREGATUM GROUP
Cuisse de Poulet echalion -- AGGREGATUM GROUP
Matador -- GARDEN ONION, BULB ONION, AGGREGATUM GROUP

The flowers attract a few nectar-feeding butterflies:
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