Gardeners have been warned that aquilegias risk being devastated by a virulent new disease.
Carrie Thomas, who holds National Plant Collections of Aquilegia, said that downy mildew was “ravaging her collection” which is based at Touchwood Plants in Swansea and was featured on BBC2’s Gardeners’ World in 2014.
While downy mildew is common on many plants, it is not known to hit aquilegia.
Carrie said there was “no published information about downy mildew on aquilegia” – and is compiling details on her website to help gardeners prevent, identify and cope with infections.
She said: “What is needed is early discovery and measures to control its spread.
“This new downy mildew of aquilegia is a very virulent disease and it is killing plants.
“The Touchwood National Plant Collections of Aquilegia may not last into the flowering season,” Carrie warned.
When plants were initially infected, Carrie had no idea what the problem was. The mystery was solved by Nigel Stringer, of the RHS Members’ Advisory Service. The RHS had received enquiries about the disease in 2013.
Carrie said it is important to find out if any treatments for the disease are effective.
For now, she recommends “immediate removal” of any plant even suspected of having the disease.
Symptoms include yellow patches on infected leaves, that have fluffy white growth on their undersides. This is most commonly seen under damp conditions.
Flowering stems can display brown/red marks, and may become distorted. Flower buds appear “blasted or blighted,” according to Carrie, on diseased plants.
Gardeners are being urged to contact Carrie if they spot any signs of downy mildew on aquilegia plants.
She can be contacted via her website, which has lots of information on the disease outbreak.
Go to www.touchwoodplants.co.uk/aquilegia-downy-mildew.htm to read more.