Guava moth has become one of the most consistent fruit pests in Northland, Auckland and Waikato gardens over the past two decades, and it's still spreading south, which means a growing number of gardeners are encountering it for the first time with no idea what they're looking at. The damage is often mistaken for general rot or a ripeness problem: fruit that drops early, sometimes weeks before it should, with a small dark entry hole and internal tunnelling that's usually already found by the time the fruit is picked up.
The moth itself is small, mottled brown and rarely seen, since it's active at dusk and through the night. What gardeners actually encounter is the damage from its larvae, cream-coloured caterpillars that hatch from eggs laid on the fruit's surface and tunnel straight in, feeding inside where no spray applied to the outside of the fruit can reach them. This is the core reason guava moth is genuinely difficult to control: by the time damage is visible, the grub causing it is already protected inside the fruit.
Feijoas, citrus and macadamias are its most common hosts in home gardens, though it will attack a wide range of soft and stone fruit when those are unavailable. Feijoa's autumn cropping window overlaps closely with the moth's active season, which is part of why feijoa growers in affected regions report it so consistently.
Feijoas, citrus and macadamias are its most common hosts in home gardens, though it will attack a wide range of soft and stone fruit when those are unavailable.
Because sprays can't reach larvae once they're inside the fruit, timing and exclusion do more work here than chemical control ever will. Picking up and destroying fallen fruit promptly, rather than leaving it to compost in place, breaks the cycle by removing larvae before they can complete their development in the soil beneath the tree. This single habit, done consistently through the whole cropping season rather than occasionally, is the most effective single control available to a home gardener.
Exclusion bagging, covering individual fruit clusters or whole small trees with fine mesh before the fruit is vulnerable, is the other genuinely reliable option, if more labour-intensive. Pheromone traps are widely sold for guava moth and are useful for monitoring when the moths are active in a given season, but on their own they catch adult males rather than meaningfully reducing the population, so they work best as an early-warning system that tells a gardener when to start bagging or when fallen-fruit collection needs to be at its most consistent, not as a control method by themselves.
The whole guava moth problem comes down to timing, since bagging or clearing fallen fruit only works if it happens before the fruit is vulnerable, not after the first grub has already been found. This site's premium check-ins are tied to a tree's actual flowering and fruiting stage, so the reminder to start protecting a feijoa or citrus tree lands while there's still fruit worth protecting.