Fruit flies
Several fruit flies lay eggs into ripening fruit. Spotted wing drosophila attacks soft fruit in Europe and North America; Queensland fruit fly attacks guavas, feijoas and citrus in Australia. Their larvae turn fruit to mush.
Pests
What it looks like
Damage shows as fruit ripens.
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Soft spots Ripe fruit softens and collapses early. -
Tiny holes Pin-prick holes where eggs were laid. -
Maggots inside White larvae inside fruit, especially berries. -
Leaking juice Fruit weeps and attracts more flies.
How to confirm it
Check fruit carefully.
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Salt water test
Soak picked berries in salty water for 30 minutes; larvae float out.
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Look for flies
Small flies with red eyes around ripe fruit.
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Late crops worst
Late-summer and autumn fruit is hit hardest.
What to do
Deny them fruit.
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Pick often
Harvest ripe fruit every day or two.
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Remove fallen fruit
Collect and destroy dropped or damaged fruit; do not compost it.
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Net with fine mesh
Cover soft fruit with insect mesh (under 1 mm) once flowering ends.
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Chill the harvest
Refrigerate picked fruit straight away to stop larvae developing.
Prevent it next time
- Keep plantings open and pruned so they dry out.
- Grow earlier-fruiting varieties that ripen before peak numbers.
- Hang monitoring traps from midsummer.
What not to do
Do not leave overripe or fallen fruit lying; it breeds the next generation.
In the growing guides
Where the guides mention it, with plant-specific advice.
Sources
- Spotted wing drosophila, Royal Horticultural Society