There are a number of legumes and vetches that grow in our yard, but most are present only through the late winter and spring, when temperatures are cooler. These have thin, soft, tendrils and lush green foliage, along with purple flowers ranging from light lavender to deep violet.
Two pea plants, however, thrive in the heat of the summer. One is scarlet pea (Indigofera miniata), a trailing groundcover perennial that grows from a large, tuberous root. This native has small, light red blossoms, and it blooms continuously throughout the summer, although the flowers tend to look rather ragged when not receiving much water.
The other plant is called partridge pea (Cassia fasciculata) and is a native annual. It germinates readily and so is easy to start from seed, and does very well in full sun. This legume produces upright stems about a foot tall, with inch-wide yellow flowers and continues blooming over a long period of time, with one flower at a time opening from any given point along the main stem. The flowers are very unusual in that one of their five petals always curls up as if deformed. It seems to usually be the same petal on all flowers - the one directly counterclockwise above the large lower petal. The leaves are slightly sensitive to the touch, closing a little when disturbed. The name comes from the fact that many birds, including game birds, eat the seeds.