The Royal Horticultural Society (RHS) is calling on gardeners to help it learn more about a new insect that is attacking agapanthus plants.
The pest, which the RHS has named ?agapanthus gall midge?, can cause deformity and discolouration of the flower buds of the plant and, in some cases, cause the flower bud to fail to open. The severity of the effects of this gall midge can range from a couple of buds failing to the collapse of the entire flower head.
The tiny agapanthus gall midge lays eggs that develop into maggots inside the individual flower buds or inside the closed flower heads as they develop. Infestation can be confirmed by the presence of creamy yellow maggots, 1mm to 3mm long.
The RHS was the first organisation to detect the agapanthus gall midge in Surrey in 2014. The pest has become established in other parts of southern England and is believed to have been present in the UK for at least two years.
Little is known about the biology and life cycle of the insect and RHS scientists hope that by enlisting the help of gardeners they can acquire more samples of affected agapanthus in a bid to learn how to tackle the pest.
The RHS is asking for samples of agapanthus flower heads that may be affected by the midge to be sent to its science team in sealed containers. Photographs of suspect plants will also prove valuable.
RHS entomologist Dr Hayley Jones said: ?We really hope UK gardeners, who are often the first to spot new pests and diseases, join forces with us, Defra and international experts to increase our knowledge of this new and potentially destructive threat to agapanthus.?
Samples should be sent to: Entomology, RHS Garden Wisley, Woking, Surrey GU23 6QB. Images, with location information (particularly postcode), which can help the RHS to map how widespread the agapanthus gall midge is in the UK, can be emailed to email@example.com.
For more information, visit https://www.rhs.org.uk/advice.