Snapdragon · Shuangcheng, Heilongjiang, China
When to sow snapdragons in Shuangcheng
Main outdoor window
12 Apr - 10 May
The window this page is built around.
Timed from last spring frost
26 April
In Shuangcheng, on your chosen risk.
Ready to pick
11 Jul - 10 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 Shuangcheng
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
15 Feb - 15 Mar
Ten weeks before your last frost, under cover or on a windowsill.
Plant out
12 Apr - 10 May
Two weeks before your last frost.
In flower
11 Jul - 10 Aug
Snapdragons through the year
Against the frost risk in Shuangcheng
Why these dates
Start indoors ten weeks before the last frost - the seed is dust-fine and needs light, so press it onto the surface rather than covering it. Plant out two weeks before the last frost, because a light frost makes the plants branch rather than harming them. Pinch the tips at 15cm for more stems.
Hardy to about -8C once established and often survives a mild winter to flower again, especially in zone 8 and warmer where autumn planting gives spring flowers. Rust is a bigger risk than cold in damp climates.
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. Snapdragons are timed from 10 weeks before that frost for an indoor start, with planting out 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Shuangcheng.
Shuangcheng 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.
The median frost-free season here is 162 days, against 90 to 120 days to first flower for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Shuangcheng
Other flowers to time
Growing snapdragons in Shuangcheng
When should I plant snapdragons in Shuangcheng?
Aim for 12 Apr - 10 May in an average year. If you would rather not gamble on the weather, wait until 21 Apr - 19 May - by then frost has finished in nine years out of ten.
When will snapdragons be ready to harvest in Shuangcheng?
Expect to start picking around 11 Jul - 10 Aug, based on 90 to 120 days to maturity from the planting date calculated for this location.
How much frost will snapdragons tolerate?
Hardy to about -8C once established and often survives a mild winter to flower again, especially in zone 8 and warmer where autumn planting gives spring flowers. Rust is a bigger risk than cold in damp climates.