The last couple of years my black-eyed Susan flowers have been snipped off as if someone has just cut off the flower. There was no trace of any bits of the flower on the ground or the plant being trampled on. I’ve lived at this property in Mississauga for 20 years and all the other flowers do not have this problem. I’d appreciate it if you could give me insight as to what might be eating my flowers. ( They are planted at different locations in the garden.)
It sounds as if you might have a very hungry rabbit coming to your property for its favorite snack. Rabbits do not like all flowers but your black-eyed Susan, (Rudbeckia hirta) is on the list of perennials that are severely damaged by rabbits. Next year you could check for evidence of rabbits: look for tracks, droppings and bite marks on your flower. Rabbits nip pencil-sized stems cleanly at a 45 degree angle. Birds on the other hand tend to shred plants and deer leave a ragged torn edge.
Many websites give advice on how to deter rabbits from eating your flowers and vegetables. I have listed two below. You might try planting alliums or other plants in the onion family between your rudbeckia. Rabbits do not like onions! Alliums come in a variety of sizes and colours. Check your local nursery.