Safe to Plant

Grecian windflower · Zhu Cheng City, Shandong, China

When to sow grecian windflowers in Zhu Cheng City

Main outdoor window

1-15 Oct

The window this page is built around.

Timed from last spring frost

31 March

In Zhu Cheng City, on your chosen risk.

Ready to pick

1 Mar - 30 Apr

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 Zhu Cheng City

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.

Plant the tubers

1-15 Oct

Four to six weeks before your first frost, so roots form before the ground cools.

In flower

1 Mar - 30 Apr

Frost tolerance
Hardy
Damaged below
-20°C (-4°F)
Days to flowering
140–180
Hardy to
Zone 5a–8b
Spacing
10 cm
Sowing depth
50 mm (2 in)
Sun
Partial

Grecian windflowers through the year

Against the frost risk in Zhu Cheng City

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

Frost risk Plant Harvest Today

Why these dates

Soak the tubers overnight before planting - they arrive bone dry and dehydrated tubers frequently fail. Plant 5cm deep in early autumn, any way up; the growing point is impossible to identify and the tuber sorts itself out.

Hardy to about -20C. Flowers early enough that a hard frost sometimes catches open blooms, which recover. Goes fully dormant by midsummer and tolerates dry summer shade better than most spring bulbs.

Grecian windflowers 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 Zhu Cheng City instead of forwards from its start.

Hardiness is not the obstacle here. Zhu Cheng City is zone 7b, comfortably inside the range this crop is rated for, so an established plant should come through an average winter without protection.

The median frost-free season here is 226 days, against 140 to 180 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 Zhu Cheng City →

Growing grecian windflowers in Zhu Cheng City

When should I plant grecian windflowers in Zhu Cheng City?

Aim for 1-15 Oct in an average year. If you would rather not gamble on the weather, wait until 20 Sep - 4 Oct - by then frost has finished in nine years out of ten.

When will grecian windflowers be ready to harvest in Zhu Cheng City?

Expect to start picking around 1 Mar - 30 Apr, based on 140 to 180 days to maturity from the planting date calculated for this location.

How much frost will grecian windflowers tolerate?

Hardy to about -20C. Flowers early enough that a hard frost sometimes catches open blooms, which recover. Goes fully dormant by midsummer and tolerates dry summer shade better than most spring bulbs.