IT always amazes me in winter, especially one as cold as this, that the pests still plague gardeners.
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I was reminded of one decimating grub last Sunday when a customer brought in her bedraggled clivia - roots and all - to see why these normally hardy plants were suffering.
The grubs that strip clumps of Clivia are often buried deep down where the foliage emerges from the soil, making it important to apply a pest killer with a watering can.
This should be done with carbaryl every 10 days - drenching and spraying as well.
Japanese box (Buxus macrophylla) and Camellia japonicas are both being affected by scale - sooty mould is often an indicator that scale is present, together with ants enjoying the sticky emission from the scale.
Treatment is necessary for the scale before the mouldy fungus is treated.
Pest oils are useful if sprayed regularly, but remember it is a preventative not a cure.
Once the scale has multiplied it is necessary to apply Antiscale or a mixture of Malathon and white oil. Follow up by spraying the sooty mould with copper oxychloride and where possible tie a rag soaked with kerosene loosely around the plant for a day or two to deter the ants that are transmitting the problems from plant to plant.
If you have pruned your roses and sprayed with lime sulphur this should eliminate any scale as well as preventing fungal diseases for months.
There is a pesky little white louse scale that is often found on palms - use Antiscale to fix this pest. Palms can also be ruined by the palm worm that hide on the leaf by folding it and stripping the end foliage - use Insect and Mite Killer, which is systemic.
Check for spider mite on azaleas, they suck out the sap, leaving the leaves with a silvery appearance.