I can't answer for zone 9 since my experience is limited, but you might want to specify where since the conditions in parts of humid Florida and parts of the desert southwest and California are both zone 9 but with quite different soils and weather.

Sacramento-ish

The hummingbirds LOVE my bottlebrush!

A few plants popular with hummingbirds here will also grow in your area, though I can't guarantee that they are the most popular. The native honeysuckle Lonicera sempervirens 'Major Wheeler' is always popular with hummers in my garden. There are other cultivars as well but I don't have experience with them. There are a range of Salvias with tubular flowers that the hummingbirds visit regularly, and you have a wide variety of native southwestern types to choose from. There are columbines/Aquilegia that will grow in your area, and the ones I grow here are some of the popular early spring flowers that the hummingbirds enjoy.

You could also ask in the California forum or the hummingbird forum.

If you want to add your city and zone to your profile so that it posts automatically by your name and we don't have to ask, here's how.

Go to Your Houzz in the upper right of every page, click Edit Profile, and on the left side click advanced settings. Well down the advanced settings page is a blank labeled Climate Zone for Garden Forums along with a link to find your zone.

If you add info on your state or the nearest large city you will get even better information since zone only relates to average coldest winter temperatures.

Then return to the top of the page and click Done Editing.

Tropical Hibiscus (hibiscus rosa-sinesis)

Not sure if this is hardy for you -- I have to grow it in pots -- but hummers go absolutely nuts for Clerodendrum speciosissimum (Giant Red Glory Bower). Many of the Clerodendrums are borderline invasive (or at least aggressive) where they are hardy though. You could always try it in a large pot to see how your hummers enjoy it!

One plant I'd love to have more of, is the pineapple sage. It grows year-round in parts of CA and attracts hummingbirds.

Does pineapple sage bloom year-round in CA?

There are so many plants that hummingbirds love, there really isn't a single "best" in California. However, Russelia rules in my SoCal garden; it is never out of bloom here. Although I have had a hummer stake out a single shrub for territory, (Leonotis menthifolia), generally multiple plants of one species provides a bigger draw.

Garden gal provides a good list. Here in Sonoma: Grevillea, Abutilon, Parkinsonia, and so may others it is hard to keep track.