Gardening with Gael - Wretched moth a danger to our fruit trees
At this time of the year my son Nicholas, in Connecticut, starts gazing across land and sea towards New Zealand, dreaming of the slowly forming feijoas and considering timing his trip home to coincide with them ripening.
Feijoas [acca sellowiana] are native to parts of South America but they are also grown in Europe, Asia, Australia and New Zealand. Here they grow really well and in our district almost everyone has feijoa trees in their gardens as specimum trees or as hedges. If not, most people have has easy access to them.
To grow feijoas the size of small hand grenades they do need food and water. Surface rooting, similar to citrus, it is easy to damage the roots. Take care with fresh animal manure. Compost it a bit first so that it doesn’t burn the roots. I have a wonderful symbiotic relationship with a girl with a horse. Twelve bags of horse manure lurk outside my house right now ready to be spread around the feijoas, citrus and asparagus during autumn when the manure has time to rot down a bit.
In the past I have mentioned a bucket of water a week and we needed that in January. This month, however there has been plenty of rain for the fruit to grow.
A problem has developed in Northland and it is slowly spreading south. The guava moth. This little moth, with a wing span of approximately 15mm (1.5cm) arrived originally from Australia. They lay their eggs at the stem and in cracks and crevices in the fruit. The entry hole, the size of a pin prick is hard to detect. The damage is similar to the codling moth but this little moth has the ability to breed all year. Feijoas aren’t the only fruit either. The guava moth will also attack guava, citrus, apples, pears and plums. Last year a number of friends discovered them in their fruit. It is devastating to lose the crop.
When visiting my friend Katy I noticed two litre milk containers hanging in her trees.
“They are guava moth traps,” she informed me, “and they seem to work.”
Here is her recipe. I tried Googling it as well and also found it on the LSB (Lifestyle Block) site along with all manner of helpful tips.
- 4 2L plastic milk containers (Yay recycling!)
- 1 litre boiling water
- 1 tsp vanilla essence
- 100g (1/3 cup sugar)
- 1 tsp vegemite (or Marmite)
- 1 tsp ammonia (the LSB site says Handy Andy is fine)
Mix together to dissolve the vegemite and sugar and allow to cool. Cut a hole in the top side of the milk container opposite the handle and push the flap in. This lets the moths in. The container hangs from the handle in tree and the angle of the container stops the rain getting in. The LSB site recommends hanging the bottles from the tree using bailing twine, which lasts longer. Keep an eye on the traps and add some fresh mixture from time to time. Katy assures me it works.
Remove all infected fruit and keep it away from compost where the larvae can flourish.
I am now sorry I’ve asked Box to keep the chooks in their run. Chickens kill the grubs as they pupate in the soil and interrupt the life cycle. Katy’s brother Colin has always recommended running chooks in orchards and controlling the guava moth is a good reason. Fencing them in around the fruit trees has many advantages.
I must let Nick know that he may still beat the moths to the feijoas.
Attacking a wide variety of fruit, the guava moth was first discovered in Northland in 1997.