My wisteria has formed buds but these are now dropping off before being fully formed. Can you please let me know what the cause of this might be? Thanks.
Certified GKH Gardening Expert
If you had a cold spell or a frost, they may have become damaged in the cold. Flowers are much more cold sensitive than the rest of the plant and will be damaged when the rest of the plant is fine.
If you have not had cold, it could be thrips. They attack the base of the flower buds and cause the buds to drop off before they are formed. This article will help if you suspect them: