Luffa · Pretoria, Gauteng, South Africa
When to plant luffa in Pretoria
Main outdoor window
7-28 Aug
The window this page is built around.
Timed from last spring frost
24 July
In Pretoria, on your chosen risk.
Ready to pick
29 Jan - 30 Apr
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 Pretoria
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
12 Jun - 3 Jul
Six weeks before your last frost, under cover or on a windowsill.
Plant out
7-28 Aug
Two weeks after your last frost.
Harvest
29 Jan - 30 Apr
Luffa through the year
Against the frost risk in Pretoria
Why these dates
Start indoors six weeks before the last frost, which is unusually early for a cucurbit, and plant out once nights hold above 15C. Sponges need around 150 frost-free days.
Killed at 0C. Fruit left to mature for sponges must dry on the vine, so a late frost ends the crop before the fibre has set.
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. Luffa are timed from 6 weeks before that frost for an indoor start, with planting out 2 weeks after it, and this page simply resolves those offsets against the frost date computed for Pretoria.
The median frost-free season here is 322 days, against 120 to 180 days to maturity for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Pretoria
Other vegetables to time
Growing luffa in Pretoria
When should I plant luffa in Pretoria?
Aim for 7-28 Aug in an average year. If you would rather not gamble on the weather, wait until 24 Aug - 14 Sep - by then frost has finished in nine years out of ten.
When will luffa be ready to harvest in Pretoria?
Expect to start picking around 29 Jan - 30 Apr, based on 120 to 180 days to maturity from the planting date calculated for this location.
How much frost will luffa tolerate?
Killed at 0C. Fruit left to mature for sponges must dry on the vine, so a late frost ends the crop before the fibre has set.