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Box tree caterpillars feed within webbing and can completely defoliate box plants. It is a relatively new insect to Britain. Whilst the adult moth was first reported in the UK in 2008, caterpillars were not found in private gardens until 2011, it has since become widespread in London and surrounding areas.
Among the thousands of plants RHS Gardening Advice receives enquiries about every year, box sits up there in our top 20 – evidence of just how popular a plant it is with gardeners. However, it is troubled by a number of pests and diseases, not least the dreaded box blight which continues to cause problems for those growing box in the UK. Box tree caterpillar is now also causing serious problems in parts of southern England.
Bracken (Pteridium aquilinum) is a common sight in the British countryside. Although less common in gardens, it can be a tough plant to remove. Issues over bracken toxicity and its use as a soil improver are also of importance to gardeners.
Bracket fungi cause decay and rot in the heartwood of trees and produce bracket-shaped fruiting bodies on the trunk or main branches. These fungi usually lead to weakening and sometimes to the eventual breakage or fall of affected trees.
Woody weeds such as brambles (Rubus fruticosus) can be difficult to eradicate once they have become established. Prompt action can prevent problems and using the right methods lightens the work of dealing with thickets of robust weeds.
Downy mildew of brassicas is a foliage disease causing whitish, fuzzy patches on the undersides of leaves and yellow discolouration on the top. It affects seedlings and mature plants.
Chocolate spot is one of the most common fungal diseases of broad beans. The fungus causes dark, chocolate-coloured spots on all parts of the plant.
Broad bean rust is one of the most common fungal diseases of broad bean leaves. The fungus causes small, dusty, dark brown spots surrounded by a pale yellow halo on leaves and stems.
Broad bean seed beetle can be a problem in dry seed, it is most likely to be seen by gardeners who save their own seed.
Brown rot is a fungal disease of apples, pears, plums, cherries and other fruit and ornamental trees, causing a brown, spreading rot in fruit. It is caused by the same fungi that cause blossom wilt of the flowers and fruit spurs.
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