How do I treate scale on my pittosporum hedge?
The hedge is Pittosporum Irene Pattison. It's about 30m long. Some plants are being attacked by scale (full on scale - so thick you can't see the stem of the plant - only scale). Some are being attacked by Pittosporum bug. I have sprayed Eco Oil as well as white oil but this only knocks a few out at a time. Is there something I can use to get rid of the whole lot? I have fed with 'complete D' as well as seasol.
What a shame - your pittosporums sound like they are in a delicate way. If the scale is that thick on the stems, the plants will be extremely vulnerable to attack on all sides. As far as controlling the scale, it may take several applications of PestOil Insecticide to get this pest population under control. It is always easier to control scale in its juvenile stage when the young are crawling. The most effective time to spray is from January to April. Spray your Pittosporums every 2 weeks until you can see some results. For controlling the bug, however, we do not have a registered product. Manually removing them and destroying them would be the safest option. As your plants will be extremely stressed, we would suggest that you give several applications of Yates Dynamic Lifter Soil Improver & Plant Fertiliser to help them to recover.
Answered: 7 Apr, 2013