Warm summer sees bean-loving bug jump into top 10 list of garden pests
The Royal Horticultural Society’s annual ranking of most garden pests and disease reveals the impacts of the hot dry weather.
An invasive bug with a taste for beans has jumped into the top 10 list of the worst garden pests as it benefited from the warm summer.
The Royal Horticultural Society (RHS) said its latest annual list of which pests and diseases are causing the most trouble in gardens revealed the impacts of the hot dry weather last summer.
The southern green shield bug, which is thought to have been introduced from mainland Europe and was established here in the 2000s, came sixth in 2018’s ranking based on inquiries to the RHS by gardeners.
Young stages of the bug are distinctively black with white or pink markings and an adult looks similar to the harmless native green shield bug but does not have a brown marking at its rear.
Pear rust is also of growing concern to gardeners, with the fungus that causes orange spots on pear leaves and canker-like swellings on juniper branches becoming very common over the last 16 years, in part due to warmer, drier summers.
But the dry conditions helped keep some problems at bay, including leaf spot and canker of Prunus and box blight, which both benefit from warm, wet weather during the growing season.
The caterpillar, which strips box of its leaves, topped the list for the worst pests for the third time, the experts said.
Despite the dry conditions, perennial pests slugs and snails were in second place in the ranking of gardener inquiries, while honey fungus topped the list of diseases again in 2018.
“With the UK predicted to see wetter winters, warmer summers and more extreme weather events, root diseases of trees and shrubs could become even more problematic and the array of pests is likely to change.
“As the UK faces new plant health problems it’s imperative that the country has the skills needed to predict, exclude and manage the worst.”
Top pests 2018:
1 Box tree caterpillar
2 Slugs and snails
3 Viburnum beetle
4 Vine weevil
5 Woolly aphid
6 Southern green shield bug
7 Fuchsia gall mite
8 Capsid bug
9 Cushion scale
10 Ants
Top diseases 2018:
1 Honey fungus
2 Phytophthora root rots
3 Pear rust
4 Volutella blight of box
5 Verticillium wilt
6 Blossom wilt of fruit trees
7 Box blight
=8 Kerria twig and leaf blight
=8 Leaf spot and canker of Prunus
10 Powdery mildew of Prunus
