Could you please tell what the disease on this Phygelius aequalis “Sensation” might be. I haven’t seen any pests on plant so have sprayed it with fungicide and tried cutting it back but it returns every year. Another phygelius – capensis – has it to a lesser extent while a third one “Moonraker” is disease free. I would appreciate your opinion.
The symptoms are very like a general lack of thrive, and this might indicate a soil problem. Phygelius is generally trouble-free, like fertile, moist but well-drained soil, overly dry soil in summer or wet in winter could be a factor. Try feeding if the soil is poor.
If the soil is okay on these counts, there only remains the possibility of some comtaminant of a chemical nature. Try to eliminate this.