An attractive accent plant available in various species and cultivars is amaranth:
When ripe, the seeds of this pseudocereal may be harvested for a delicious and nutritious dish, or saved to plant for next year’s enjoyment by garden guests. Meanwhile, the leaves—also edible by people and other creatures—serve to add additional visual texture for us and a landing pad for small fliers
while the tiny flowers attract pollinators and perhaps predators
some of which (as insect vision typically differs in spectral range from ours, or that of other animals) may stand out more than is good for them: