Here are three things that seem to work in reducing guava moth numbers significantly.
So if, like me, you have feijoas or peaches or any other fruit tree and you’re having a problem with guava moth, try these suggestions. I’ve spoken to several people in my community who have been also having problems and the combination of these three strategies really seems to work :o)
Put pheremones in trees – Asian Peach Moth (PFM 80798 Shinkuicon-L) – you can buy packs of 250 ties from Fruit Fed (originally from Shin-Etsu Chemical Company Ltd., Japan). Tie one tie per tree (with a ribbon so you don’t lose it and accidentally prune it off!) in the top branches on the southern side of the tree and around the perimeters of your orchard. I just tied them on when I bought them (so I can’t recommend a particular time of year). Each tie should last 12-14 months though (and you may need to find other growers to share that number of ties with to make it cost effective).
Hang a mixture in cut-off milk bottles in your trees to catch existing moths; the moths should be attracted to it and then drown in it. Take 1 litre of boiling water, add 1/3 cup sugar, 1 tsp vanilla essence, 1 tsp marmite and 1 tsp ammonia (e.g. Handy Andy). Mix the ingredients and dissolve then allow to cool. Cut a flap into the side of the milk bottle with the hinge at the bottom, so you can push the flap inwards. Hang up in your tree with baling twine and refill as necessary
Pick up diseased fruit and freeze (before putting in the compost). The larvae pupate in the fruit so it is really important to pick up any fruit off the ground and dispose of it. You can’t just put it into your compost, as the larvae will just continue to grow, so you need to either freeze the fruit first (for at least 24 hours) or feed it to livestock (like pigs) who will eat the fruit and larvae all up.