Gardenia jasminoides var. ....

This gorgeously-scented flower has a heavy sweetness associated more with the tropics, to which it is native, than the many unexpected places it grows such as this particular specimen blooming in front of my apartment. Called zhi zi in Chinese medicine, it is quite commonly used to clear heat in wide variety of manifestations, from infections to insomnia and topical inflammation.

Purslane, Portulacca oleracea

Although considered primarily a weed here in the U.S. this humble, low-growing plant is valued as a nutrient-rich salad green (eaten raw or cooked) and for its medicinal qualities in many other countries. Its use in both regards dates back to ancient time and particularly in Greeece archaeobotanical evidence of this plant has been found. Purslane has a delicious if slightly sour flavor and is quite unusual for its high content (more than any other leafy green) of omega-3 fatty acids, which are most commonly found in seeds and in fish.

California Poppy, Escholtzia californica

This California native, designated in 1890 as the California State flower, is a relative of the more famous (and more potent) Papaver somniferum also called the opium poppy. While the latex from the P. somniferum capsule is processed into opium, it's the roots of E. californica, also a golden-orange hue, that can be made into a tincture or tea and is an excellent remedy for insomnia.

Wild lettuce, Lactuca virosa

This relative of salad lettuce, while edible, is incredibly bitter. The milky latex which is visible when a stem or a leaf is broken, called lactucarium, resembles opium latex in both in appearance and effect and was widely used as a (milder) substitute when opium was unavailable. One of the most common uses for Lactuca is for sleep and an herbalist friend of mine would run the whole plant through her juicer, then dehydrate, powder and encapsulate, to excellent (if not labor-intensive) effect.

Kumquat, Fortunella japonica

Ceanothus (most likely) spinosus

The flowers, fresh or dried, contain saponins and can be used for their mild soapy qualities. It's the very tough roots however that are an unsung, very easily-found medicine, with a particular affinity for the lymph system and nodes. The tincture or a strong decoction can be used as a gargle for acute tonsillitis and as an adjunct herb internally for both mastitis and mononucleosis. Due to its anticoagulant properties this plant medicine is contraindicated for people on anticoagulants or with coagulation disorders.

Passiflora incarnata

Simply one of the best remedies for insomnia that I know of, Passiflora contains some interesting alkaloids, specifically harmalines, also found in syrian rue (Peganum harmala) and Banisteriopsis spp. (an ingredients in ayahuasca). While Passiflora is generally a safe herb to take, I recommend caution with people on MAO-inhibitors and similar medications.