How does a high-tech garden grow?

All across the country economic development officials are eager to take cuttings, so to speak, from Honeywell and Digital Equipment and Intel and other well-established high-tech companies.

But Elliott Bouillion argues that the best way to have a flourishing electronics industry is to grow your own - from seed.

He also suggests that the state of Louisiana is going to take some spadework and weeding if it is going to be a fruitful field for high technology.

Phoenix Computer Graphics, of which he is vice-president, grew out of work done at the University of Southwestern Louisiana, his alma mater. This 22-person company, launched in 1979, designs and makes (with purchased components) very high-resolution, three-dimensional color graphic computers.

Its product, the Phoenix 1024, has applications in the energy industry, notably for seismic work; aerospace; and meteorology, to name three. Phoenix customers include Ford Aerospace and General Electric.

One of Mr. Bouillion's frustrations is that although Phoenix computers have such natural applications to southern Louisiana's energy industry, people here just aren't computer minded yet - or computer funded, for that matter. He says 82 percent of his customers are outside the South.

Despite its small size, Phoenix is regarded as ''the darling'' of the Lafayette high-tech community. It did $1.5 million in sales last year; $7 million is expected this year. One big feather in its cap: a contract to supply 10,000 highly specialized circuit boards over five years to a California semiconductor firm, which will use them in one of its own products.

Still, Mr. Bouillion, a dark-haired, bearded young man in the gray pin-striped mode that seems to be replacing jeans as the high-tech uniform, describes his firm frankly as ''struggling.'' The problem, he says, is ''l'argent'' - money - and the recession.

But longer term, he expresses concern about how well positioned Louisiana will be to absorb the overflow of electronics industry out of California and Massachusetts.

The trend will be Sunbeltward, but not indiscriminately: ''We're going to have to be fast and aggressive. The states that are going to get this are the ones that are prepared.''

Louisiana does not yet have a one-stop state agency to facilitate movement of high-tech into the state, he says. ''If I want to go into Research Triangle Park (in North Carolina), I can go to one place and get it all.''

The lack of venture capital in the state is widely recognized as another drawback to the launching of new businesses here. That hurdle may be lowered, however, if not removed, if a proposal of the gubernatorial task force on high-tech is enacted. The group is submitting in this legislative session a bill to establish a private, for-profit venture capital partnership into which investors would be induced by tax credits.

Back in Lafayette, Mr. Bouillion praises the business community's commitment to a 100-acre electronics park, but adds, ''They've knocked on a lot of doors, but they still haven't got a large firm yet.'' He expresses reservations, anyway , on recruitment from outside: ''You've got to build from the ground up. They couldn't expect to get a Hewlett-Packard in here.''

The state as a whole has been more interested in seeking remote manufacturing plants than R&D operations - a reflection of ''human capital'' limitations in Louisiana. And yet there are some research operations in the state, and they seem to be doing fairly well. The California-based Litton Industries Data Systems division has had a design center in New Orleans for three years. New Orleans was chosen for its living costs and available labor pool, according to Gene Berryman, director of electrical engineering. Of the 275 employees there, nearly 200 are engineers, he estimates. Litton hired its staff largely from California, and indeed, the country as a whole, but Mr. Berryman reports that satisfactory employees have been hired from among engineering graduates of Tulane and the University of New Orleans. ''We advertised nationwide, and we got a lot of people who were originally from Louisiana but had to go elsewhere to find jobs.''