Dame's rocket

Questions about dame's rocket

Does dame's rocket need sun or shade?

Dame's rocket grows in full sun (6 or more hours of direct sun a day), part sun (4 to 6 hours of sun, including some afternoon sun) and part shade (2 to 4 hours of sun, mostly in the morning).

It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells. Once settled in, it stands drought.

What zones does dame's rocket grow in?

USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °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 dame's rocket flower in my zone?

In zone 5 it flowers mid May to late June. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.

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 dame's rocket be planted?

16 in (40 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 18 in (45 cm), so a group knits into one patch.

It grows 3 ft (90 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.

How many dame's rocket plants do I need?

At 16 in apart, set out in staggered rows:

• 7 to fill 10 square feet (about 1 m²)
• 8 for a single row 10 ft (3 m) long
• 21 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.

Is dame's rocket poisonous to dogs and cats?

No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.

"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.

What can I plant instead of dame's rocket?

Dame's rocket is listed as invasive in parts of North America (3 listings), so the planner never uses it. These do the most similar job, and are native:

• Beardtongue 'Husker Red': the same job in a bed, the same size and the same flowering time; white, not purple.
• Ohio spiderwort: the same job in a bed, the same size and the same flowering time; blue, not purple, fine leaves, not medium.
• Purple milkweed: the same job in a bed, the same size and the same colour; flowers early June to mid July, bold leaves, not medium.

Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.

Do deer eat dame's rocket?

Mostly not. NC State lists it as resistant to deer. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.

Will dame's rocket spread?

It seeds itself about; the risk of it taking over is high. Self-seeds prolifically and invades woodland edges and wet meadows. Listed as invasive across much of the Northeast and Midwest, and banned from sale in Colorado, Connecticut and Massachusetts.

It is listed as invasive in parts of North America, and the planner never chooses it.

What flowers after dame's rocket?

Dame's rocket is over by late June. These start as it finishes and carry the same spot on, so it never goes flat:

• Astilbe: from late June to mid July, 24 in tall, to stand in front of it and cover its fading stems.
• Black-eyed Susan: from mid July to mid September, 24 in tall, to stand in front of it and cover its fading stems.
• Butterfly weed: from late June to early August, 24 in tall, to stand in front of it and cover its fading stems.

What does dame's rocket look like in winter?

Dame's rocket dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.

Is dame's rocket good for bees and butterflies?

Dame's rocket is visited by butterflies and moths.