Nodding onion

Questions about nodding onion

Does nodding onion need sun or shade?

Nodding onion grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).

It wants ordinary well-drained soil, of average fertility, and little watering once settled. Once settled in, it stands drought.

What zones does nodding onion grow in?

USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).

Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.

Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.

When does nodding onion flower in my zone?

In zone 5 it flowers early July to early August. As a summer flower it moves about half a week for every zone: earlier where it is warmer.

Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.

How far apart should nodding onion be planted?

8 in (20 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 10 in (25 cm), so a group knits into one patch.

It grows 18 in (45 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.

How many nodding onion plants do I need?

At 8 in apart, set out in staggered rows:

• 27 to fill 10 square feet (about 1 m²)
• 16 for a single row 10 ft (3 m) long
• 86 to fill a 4 × 8 ft bed on its own

In a mixed border, plant it as a group of three or five, with a second group further along in the other number.

In the bed above, the planner used eight in two groups.

Is nodding onion poisonous to dogs and cats?

Yes: moderate toxicity to dogs, cats and horses. Like all onions, it can damage red blood cells in dogs, cats and horses if eaten.

Rated from NC State Extension. Where references disagree, the more cautious rating is used.

Do deer eat nodding onion?

They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.

Will nodding onion spread?

It seeds itself about; the risk of it taking over is moderate. Self-seeds freely. Remove the spent flowers to limit seedlings.

What flowers after nodding onion?

Nodding onion is over by early August. These start as it finishes and carry the same spot on, so it never goes flat:

• Prairie dropseed: from mid August to mid September, 2½ ft tall (a recorded partner).
• Lilyturf: from early August to mid September, 16 in tall.
• Japanese anemone: from mid August to early October, 3 ft tall.

What does nodding onion look like in winter?

Nodding onion dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.

Is nodding onion good for bees and butterflies?

Nodding onion is visited by pollinators, bees, butterflies, hummingbirds, beneficial insects and songbirds.

It is native to the United States and Canada.