Safe to Plant

Zinnia · Regina, Saskatchewan, Canada

When to sow zinnias in Regina

Main outdoor window

21 May - 4 Jun

The window this page is built around.

Timed from last spring frost

14 May

In Regina, on your chosen risk.

Ready to pick

20 Jul - 9 Aug

If you plant at the start of the window.

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

Step by step in Regina

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.

Start indoors

16-30 Apr

Four weeks before your last frost, under cover or on a windowsill.

Sow direct

21 May - 4 Jun

One week after your last frost.

Plant out

21 May - 4 Jun

One week after your last frost.

In flower

20 Jul - 9 Aug

Sow in succession. A single sowing gives you a single glut. Sow a short row every 21 days through the window above and you get a steady supply instead.
Frost tolerance
Tender
Damaged below
0°C (32°F)
Days to flowering
60–80
Min soil temp
21°C (69.8°F)
Spacing
25 cm
Sowing depth
6 mm (0.2 in)
Sun
Full

Zinnias through the year

Against the frost risk in Regina

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

Frost risk Start indoors Sow direct Plant out Harvest Today

Why these dates

Direct sowing after last frost usually beats transplanting - zinnias dislike root disturbance and catch up quickly.

Killed by the first frost at either end of the season. Strictly a warm-season flower.

Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Zinnias are timed from 4 weeks before that frost for an indoor start, with planting out 1 weeks after it, and this page simply resolves those offsets against the frost date computed for Regina.

The median frost-free season here is 137 days, against 60 to 80 days to first flower for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.

See every crop timed for Regina →

Nearby

Zinnias in places close by

Growing zinnias in Regina

When should I plant zinnias in Regina?

Aim for 21 May - 4 Jun in an average year. If you would rather not gamble on the weather, wait until 1-15 Jun - by then frost has finished in nine years out of ten.

When will zinnias be ready to harvest in Regina?

Expect to start picking around 20 Jul - 9 Aug, based on 60 to 80 days to maturity from the planting date calculated for this location.

How much frost will zinnias tolerate?

Killed by the first frost at either end of the season. Strictly a warm-season flower.