Lettuce · Thembisa, Gauteng, South Africa
When to plant lettuce in Thembisa
Main outdoor window
15-29 Jul
The window this page is built around.
Timed from last spring frost
5 August
In Thembisa, on your chosen risk.
Ready to pick
29 Aug - 13 Sep
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 Thembisa
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
24 Jun - 8 Jul
Six weeks before your last frost, under cover or on a windowsill.
Sow for autumn
2-23 Mar
Counting back 74 days from your first frost so the crop matures in time.
Sow direct
15-29 Jul
Three weeks before your last frost.
Plant out
22 Jul - 5 Aug
Two weeks before your last frost.
Harvest
29 Aug - 13 Sep
Lettuce through the year
Against the frost risk in Thembisa
Why these dates
Sow every ten days from six weeks before last frost. Pause through midsummer, then resume for an autumn crop - late sowings are often the best of the year.
Tolerates -3C and a light frost actually sweetens the leaf. Seed germinates poorly above 25C, which is the more common problem.
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. Lettuce are timed from 6 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 Thembisa.
The median frost-free season here is 304 days, against 45 to 60 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Thembisa
Other vegetables to time
Growing lettuce in Thembisa
When should I plant lettuce in Thembisa?
Aim for 15-29 Jul in an average year. If you would rather not gamble on the weather, wait until 9-23 Aug - by then frost has finished in nine years out of ten.
When will lettuce be ready to harvest in Thembisa?
Expect to start picking around 29 Aug - 13 Sep, based on 45 to 60 days to maturity from the planting date calculated for this location.
How much frost will lettuce tolerate?
Tolerates -3C and a light frost actually sweetens the leaf. Seed germinates poorly above 25C, which is the more common problem.