The most troublesome garden and greenhouse disease in the UK last year has been identified as honey fungus.
Caused by a number of different types of Armillaria fungi, the disease attacks the roots of woody and perennial plants, the Royal Horticultural Society (RHS) revealed.
The organisation identified the problem as being the biggest issue affecting gardeners during 2009 after studying records of the enquiries taken by its members.
Hellebores, roses and primulas are also often affected by rose black spot – a strain of fungal leaf spots, which was also among the most troublesome diseases of last year for British growers.
Meanwhile, the body identified powdery mildews caused by fungi as being a particularly problematic issue for gardeners.
The disease can be identified by a white, dusty coating on flowers, stems and leaves and is among the five most bothersome illnesses suffered by UK plants in the past year.
In other news, the RHS has reassured gardeners that the risk of contracting Legionnaires disease from potting compost is very low.
Responding to media reports, it said that the illness is more commonly associated with areas of standing water.