The Red Buckwheat is one of the most bulletproof plants we know for the Southern California garden. Although normally from locations further north and around the coast, it is perfectly happy in clay soil with full sun and little water here in Sherman Oaks. Everyone we have turned onto this plant has come back with glowing reports.
Unlike many other buckwheats, it is evergreen, forming a nice, dense 1–2 foot mound (although they are less neat in the shade). As a bonus, small butterflies like to nectar on it, including the Acmon Blue, Large White Skipper, and others.
The color of this long-blooming plant can be hard to pin down. A darker pink color is often sought after, although most plants shade more towards pale to middle pink. They hybridize freely with their close relative, the white-flowered single-bloomed Eriogonum grande var. grande (which we had for a while); the results are often plants with pale pink flowers, and tall, widely-branched inflorescences that can be as large as the plant underneath!
Propagation: Red Buckwheat is nice in a mass planting, particularly along border edges; fortunately for the budget, it's easy to grow from seed. We buy ours from the Santa Barbara Botanic Garden; each seed packet would produce hundreds of plants, so we seed about a quarter packet at a time. They should germinate well at almost any time of the year (except the cold winter months).