Not only does California have the largest population of any state in the union; it also produces politicians of a rare and exotic flavor matching the fruits and flowers that grow in such profusion in this empire of the West. After all, California gave us Richard Nixon, who, following his disgrace and resignation from the presidency, holed up in his estate at San Clemente on the Pacific in Southern California.

The present governor, Edmund G. Brown Jr - "Jerry", as he prefers to be called - is a rara avis in the tradition of the colorful past. Unmarried and with a Jesuit education transposed to Zen and meditation, he lives a low-key life. Spurning the showy perquisites such as the shiny black limousine and the newly built $2.5 million governor's mansion, he in his respect resembles President Carter.

It would be hard to imagine another state in which a Jerry Brown could be elected to the higest office. Yet when he ventured outside California last year he won five presidential primaries in a row - one in Maryland, where he was scarcely known. He entered late and those familiar with the whole primary clutter believe that if he had come in 30 days earlier he would have won the Democratic nomination.

Trying to explain Brown's popularity is far from easy. It may be his youth - he is only 37. Part of it is the image he has established of the nonestablishment, nonpolitical figure. A new face, a new kind of man, he just may have something to offer.

Yet his critics, including many long-time Democrats, say that he has done nothing. He is coasting, they say, with the low profile that keeps him out of controversy. But he has pared the cost of state government and one result is a surplus well over $2 billion. In part this was an inheritance from his predecessor, Gov. Ronald Reagon.

Next year Brown comes up for reelection, and it is no accident that his raiting in the polls is roughly 4 to 1 against any visible Republican opponent. It is not that the Republicans lack aspirants. Their concern is that in a good old-fashioned donnybrook in the Republicans primaries next June they will cut each other to pieces, moderates v. conservative, hard-liners v. soft-liners.

The candidate favored by the moderates, who believe he has the best chance to win against Brown, is Mayor Pete Wilson of San Diego. At 43, he has won a reputation for running an efficient, government, and with it a state-wide name.

Wilson is already pushing his campign hard, speaking up and down California to audiences that seem to like his friendly, clean-government style. He told me in the course of a long talk that Ronald Reagon has promised to remain neutral.

At the same time, some of Reagon's big-money backers are ready to help support Wilson's primary campign. Which will cost not less than a million dollars, most of it going for television.

Next in consideration is Evelle Younger, currently serving his second term as attorney general. With a law-and-order reputation, Younger is well to the right of Wilson. Most important, he has a name familiar to most Californians who pay any attention to politics.

The joker in the deck is Los Angeles Polics Chief Ed Davis. He is a real hard-liner whose views appeal to Republican right-wingers with a yearning for the good days before the environmentalists and civil-rights crusaders threw their weight into one controversy after another. Whether Davis will get into the race is still uncertain.

A lot can happen between now and next June, and the governor may find some boobytraps planted along the way. One is an initiative likely to be on the ballot in the primary election.

Plotted by State Sen. John V. Briggs, it would ask "yes" or "no" as to whether homosexuals should be allowed to teach in the public school system. Rapidly becoming the Anita Bryant of California. Briggs flew to Miami, volunteering his services to help her defeat the city ordinace granting civil rights to the gays. Rumor have it that she is ready to come here to help Briggs put over his initiative by the petition method.

If Brown opposes the proposition he will outrage the right thinking citizenry. Declaring for it, however half-heartedly, he will offend young civil-righters and the gay community, which is said to be larger in California than in any other state.

Since Brown's ambition is not limited to reelection as governor, this could cast a long shadow on the future. in 1984 he will be 43, and if all goes well he could be a prime candidate for the presidency.