Top was slugs and snails and in second place were harlequin ladybirds, third place went to the scarlet lily beetle, with vine weevil and chafer grub fourth and fifth.
RHS principal entomologist Andrew Halstead said: ‘'Adult harlequin ladybirds and their larvae feed mainly on greenfly and other aphids, so are helpful to gardeners. They will eat other insects if aphids are in short supply but it remains to be seen whether the arrival and spread of this new ladybird will have an undesirable impact on other aphid predators."
The plants that produced the greatest number of pest enquiries were lawns, apples, Viburnum, lilies and pears,
The main lawn problems are chafer grubs, moles, leatherjackets, ant nests and worm casts.
Halstead said: "Chafer grubs can be a severe problem for lawns, especially on sandy or chalky soils. The beetle grubs sever the grass roots, allowing foxes, badgers and crows to rip up the loosened turf in the autumn and winter. These animals eat chafer grubs and so provide some control but the lawn can end up looking like a badly ploughed field."
Horse chestnut leaf-miner moth fell off the top 10 enquiries list after being second in 2008, while cushion scale, cypress aphids and rosemary beetles also disappeared.
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