Apple and pear sucker - The suckers are often first spotted by the black sooty mould on the leaves. Control the sucker with Hallmark with Zeon Technology (only approved for pears with a seven-day harvest interval) or Decis (approved for both apples and pears) and control the sooty mould with Rovral WP. The mould will be removed by the next rain or irrigation application.
Fremontodendron - I suggest an application of Aliette 80WP is given to Fremontodendron plants in August to control aerial Phytophthora that often occurs on the stems. Also include Euphorbia in the spray programme. Increases of this disease can be linked to periods of wet, humid weather.
Pine shoot moth - Remember to apply Toppel 10, Dusrban WG or Gyro now to control grubs. Check for gumming around buds and stunted leader growth.
Moths - Travelling back late at night I have seen really high numbers of moths, which is an indication that we should be vigilant for the types that can attack ornamentals (leopard, swift and tortrix moths among others). Check those plant species that you know are vulnerable, particularly under protection.
Aphids - Are you keeping your aphid populations under control with biological control? Make sure you are using the right predator and check which aphid you are targeting. If you find that you are still not getting good control consider adding Adalia to the crop. This is an ideal product to support an Aphidius programme.
Bark-boring beetles - There are several bark-boring beetles, which all have a similar life cycle. Adults lay eggs from July to October, depending on the season, by boring a small hole under a joint or leaf axil; the eggs then hatch out and bore into the wood. The beetles eat their way out of the tree leaving the tell-tale sawdust marks in the following spring/summer. If you have seen this problem it points to trees that are under stress, as healthy trees rarely seem to contract them. Control adults by spraying Dursban WG on the stem area.
Shot hole - Switch the copper fungicide to Cuprokylt now. The foliage on Prunus subjects is now strong enough to take the more aggressive product. Spray cherries every two weeks to clean up the foliage before leaf drop.
John Adlam is the managing director of Dove Associates