Zinnia · Newcastle upon Tyne, England, United Kingdom
When to sow zinnias in Newcastle upon Tyne
Main outdoor window
23 Apr - 7 May
The window this page is built around.
Timed from last spring frost
16 April
In Newcastle upon Tyne, on your chosen risk.
Ready to pick
22 Jun - 12 Jul
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 Newcastle upon Tyne
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
19 Mar - 2 Apr
Four weeks before your last frost, under cover or on a windowsill.
Sow direct
23 Apr - 7 May
One week after your last frost.
Plant out
23 Apr - 7 May
One week after your last frost.
In flower
22 Jun - 12 Jul
Zinnias through the year
Against the frost risk in Newcastle upon Tyne
Why these dates
Direct sowing after last frost usually beats transplanting - zinnias dislike root disturbance and catch up quickly.
Killed by the first frost at either end of the season. Strictly a warm-season flower.
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. Zinnias are timed from 4 weeks before that frost for an indoor start, with planting out 1 weeks after it, and this page simply resolves those offsets against the frost date computed for Newcastle upon Tyne.
The median frost-free season here is 219 days, against 60 to 80 days to first flower for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Newcastle upon Tyne
Other flowers to time
Growing zinnias in Newcastle upon Tyne
When should I plant zinnias in Newcastle upon Tyne?
Aim for 23 Apr - 7 May in an average year. If you would rather not gamble on the weather, wait until 13-27 May - by then frost has finished in nine years out of ten.
When will zinnias be ready to harvest in Newcastle upon Tyne?
Expect to start picking around 22 Jun - 12 Jul, based on 60 to 80 days to maturity from the planting date calculated for this location.
How much frost will zinnias tolerate?
Killed by the first frost at either end of the season. Strictly a warm-season flower.