Dahlia · Jilin, Jilin, China
When to sow dahlias in Jilin
Main outdoor window
12 May - 9 Jun
The window this page is built around.
Timed from last spring frost
28 April
In Jilin, on your chosen risk.
Ready to pick
1 Jul - 31 Oct
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 Jilin
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
12 May - 9 Jun
After the last frost, once the soil has warmed. This crop is never fully dormant, so it cannot be planted bare-root in winter.
In flower
1 Jul - 31 Oct
Dahlias through the year
Against the frost risk in Jilin
Why these dates
Plant tubers two weeks after your last frost, once the soil has reached about 13C, 15cm deep with the crown upward. For earlier flowers, start them in pots under cover six weeks before that and plant out as growing plants. Pinch the leading shoot at 40cm to get a bushy plant rather than one tall stem.
Top growth is blackened by the first touch of frost at about -1C, which is what ends the season. The tuber below ground survives a light frost but not a frozen soil, so in zone 7 and colder lift it a week or two after the tops are killed, dry it off and store it somewhere frost-free.
Dahlias are planted once and then left in place, so there is no sowing offset to resolve. Nor is there a dormant season to plant into: this crop keeps its leaves and keeps growing through the winter, which is exactly why cold damages it. The window on this page therefore waits until the last frost in Jilin has passed and the soil has begun to warm, giving the roots the longest possible run before the cold returns.
Jilin sits in zone 4b, 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.
Also in Jilin
Other flowers to time
Growing dahlias in Jilin
When should I plant dahlias in Jilin?
Aim for 12 May - 9 Jun in an average year. If you would rather not gamble on the weather, wait until 20 May - 17 Jun - by then frost has finished in nine years out of ten.
When will dahlias be ready to harvest in Jilin?
Expect to start picking around 1 Jul - 31 Oct, based on 80 to 110 days to maturity from the planting date calculated for this location.
How much frost will dahlias tolerate?
Top growth is blackened by the first touch of frost at about -1C, which is what ends the season. The tuber below ground survives a light frost but not a frozen soil, so in zone 7 and colder lift it a week or two after the tops are killed, dry it off and store it somewhere frost-free.