Guava moth

Active spring through autumn, September to May, with overlapping generations, mainly in the upper North Island.

Guava moth is a moth that spread through the upper North Island and attacks a wide range of home fruit including feijoa, citrus, plum, peach, loquat, macadamia and nashi. The larvae bore inside the fruit, leaving it rotten and maggoty, and there is no quick spray fix, so timing and hygiene are everything.

How to identify

• Small speckled black and white moths about 15mm across
• Tiny entry holes near the stem or blossom end of the fruit
• Pink larvae up to 8mm tunnelling and feeding inside the fruit
• Brown rot and frass around the tunnels when fruit is cut open
• Premature fruit drop and fruit that rots on the tree

How to prevent

• Wrap or bag ripening fruit in fine mesh once it is green but before it colours
• Pick up and dispose of all fallen fruit at least twice a week, since larvae pupate in it
• Keep the ground under trees clear of grass, weeds and leaf litter
• Stagger or thin to a few well-managed trees rather than many neglected ones
• Harvest fruit a touch early and ripen it indoors when pressure is high

How to control organically

• Hang pheromone traps from spring to monitor flights and time other measures
• Apply neem granules to the soil under trees in winter to hit overwintering larvae
• Spray Btk over the foliage and fruit in spring and summer during egg hatch, repeating after rain
• Bag fruit as the most reliable protection where moth pressure is high
• Collect, bag and bin every dropped and infested fruit to break the cycle