Snapdragon · Nanjing, Jiangsu, China
When to sow snapdragons in Nanjing
Main outdoor window
28 Feb - 28 Mar
The window this page is built around.
Timed from last spring frost
14 March
In Nanjing, on your chosen risk.
Ready to pick
29 May - 28 Jun
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 Nanjing
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
3-31 Jan
Ten weeks before your last frost, under cover or on a windowsill.
Plant out
28 Feb - 28 Mar
Two weeks before your last frost.
In flower
29 May - 28 Jun
Snapdragons through the year
Against the frost risk in Nanjing
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 Nanjing.
Hardiness is not the obstacle here. Nanjing is zone 8b, 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 258 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 Nanjing
Other flowers to time
Growing snapdragons in Nanjing
When should I plant snapdragons in Nanjing?
Aim for 28 Feb - 28 Mar in an average year. If you would rather not gamble on the weather, wait until 12 Mar - 9 Apr - by then frost has finished in nine years out of ten.
When will snapdragons be ready to harvest in Nanjing?
Expect to start picking around 29 May - 28 Jun, 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.