You can try "Derris Dust" available from Hardware stores and Nurseries. It is an insecticide made from the powdered tuberous roots of certain Derris plants. Apply the powder according to instructions on the packaging. After rain you will have to reapply the "Dust" to your plants. I hope I have been of some help. Good luck. Barbara.

 Thanks so much. I will definitely try it as I feel sad that the Geraniums are producing such great buds that never get a chance to open to beautiful blooms. Fingers crossed.