Mexican Fleabane is a lovely little daisy-like flower that self-seeds but is not too invasive.
Flowers almost all year long. Looks stunning when in a large clump.
Very happy in full sun and dry sandy soil. Rockeries are ideal but will also grow happily in pots and containers.
Not only does it attract hoverflies, many other insects love it ranging from various flies to butterflies, crickets and even lacewing larvae.