Grecian windflower · Kostroma, Kostroma Oblast, Russia
When to sow grecian windflowers in Kostroma
Main outdoor window
25 Aug - 8 Sep
The window this page is built around.
Timed from last spring frost
10 May
In Kostroma, 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 Kostroma
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
25 Aug - 8 Sep
Four to six weeks before your first frost, so roots form before the ground cools.
In flower
1 Mar - 30 Apr
Grecian windflowers through the year
Against the frost risk in Kostroma
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 Kostroma instead of forwards from its start.
Kostroma sits in zone 4a, which is colder than this crop is rated for, so it will need winter protection or a container that can be moved under cover. The dates below still describe the right time of year; the open question is survival rather than timing.
The median frost-free season here is 149 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.
Nearby
Grecian windflowers in places close by
Also in Kostroma
Other flowers to time
Growing grecian windflowers in Kostroma
When should I plant grecian windflowers in Kostroma?
Aim for 25 Aug - 8 Sep in an average year. If you would rather not gamble on the weather, wait until 11-25 Aug - by then frost has finished in nine years out of ten.
When will grecian windflowers be ready to harvest in Kostroma?
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.