Safe to Plant

Crown imperial · Rabat, Rabat-Salé-Kénitra, Morocco

When to sow crown imperials in Rabat

Main outdoor window

not outdoors here

The window this page is built around.

Timed from last spring frost

no spring frost

In Rabat, on your chosen risk.

First autumn frost

no autumn frost

The far end of the outdoor season.

The average last frost. Half of all years are later than this.

Step by step in Rabat

Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.

Frost tolerance
Very-hardy
Damaged below
-25°C (-13°F)
Days to flowering
160–200
Hardy to
Zone 5a–8a
Spacing
30 cm
Sowing depth
200 mm (7.9 in)
Sun
Full

Crown imperials through the year

Against the frost risk in Rabat

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Frost risk Today

Why these dates

Plant in early autumn, as early as the bulbs can be bought, and deep - 20cm. The bulbs have a hollow crown that collects water and rots, so plant them at a slight tilt or on a handful of grit. They resent disturbance and often skip a year after being moved.

Hardy to about -25C. The smell deters mice and voles, which is a genuine advantage in a garden where tulips get eaten. Needs cold winters and dislikes hot wet summers.

Crown imperials are anchored to the first autumn frost rather than the last spring one, so the planting window on this page counts backwards from the end of the season in Rabat instead of forwards from its start.

Rabat sits in zone 11b, which is milder than this crop wants, and a winter that never really arrives is its own problem. The dates below still describe the right time of year; the open question is survival rather than timing.

See every crop timed for Rabat →

Growing crown imperials in Rabat

How much frost will crown imperials tolerate?

Hardy to about -25C. The smell deters mice and voles, which is a genuine advantage in a garden where tulips get eaten. Needs cold winters and dislikes hot wet summers.