In the front yard of her Long Beach, Calif., home, Jennifer van der Fluit has cultivated a small but bountiful vegetable garden. Lettuces, bitter greens and a giant tangle of onion shoots flourish alongside carrots, Chinese cabbage and other cool-weather varieties.

“My son loves turnips — whatever! Right?” chuckles the mother of two, ages 5 and 8, as she navigates the wide, mulched pathways between the raised beds she’s divided into a series of square-foot grids.

Van der Fluit, 44, practices what is known as square-foot gardening.

Developed in the early ’80s by retired civil engineer Mel Bartholomew, the method is designed to produce a large amount of food in a small amount of space, in only six inches of soil, while eliminating the wasteful practices of traditional row gardening, including over-seeding, overproduction and thinning.

GROW WHAT YOU NEED

“Most people who do row gardening end up with far more produce than they’ll ever use,” says Jerry Nielsen, a 72-year-old certified square-foot gardening instructor from Pasadena. “With square-foot gardening, you can really plan in such a way so that the produce you grow can be staggered. When one plant is gone the next one is already coming along.”

The method almost ensures success. So it’s no surprise square-foot gardening is taught to people in developing countries (through Bartholomew’s nonprofit foundation aimed at ending world hunger) as well as to home gardeners through a network of certified instructors listed at www.squarefootgardening.org.

IT’S FOOLPROOF

For starters, it uses a carefully prepared soil dubbed Mel’s Mix — one part each of peat moss, vermiculite and compost — and a grid system that controls how much food is planted, produced and harvested.

Depending on the desired crop, one square foot grid can accommodate 32 radishes, 16 beets or one tomato plant in just six inches of soil, without crowding.

“I love this method because I can be easily overwhelmed, and so it helps me concentrate on one square at a time,” says van der Fluit, who gave up long, single row gardening several years ago after reading Bartholomew’s guide, “All New Square Foot Gardening.”

The second edition of the book is due out Feb. 15 with an expanded section on vertical gardening and tips on pest control.

But the principles have not changed.

The raised grids should be no wider than 4 feet-by-4 feet. Otherwise, gardeners run the risk of stepping on the soil and compacting it.

There’s no need to till, dig or fertilize the soil.

And gardeners should plant only the number of seeds or starters they think they’ll need.

Nielsen has taken those principles and is in the process of adapting them to a patio garden.

“Arthritis and age have been making it harder to walk up to my upper yard and tend to my gardens,” he says. “So I’m going to bring my beds down to the patio, put a bottom on them, and put them on legs so I can continue my square foot gardening down where I don’t have to work off of these old knees.”

SIMPLIFY, SIMPLIFY, SIMPLIFY

Van der Fluit admits she’s not entirely a purist.

“I’ve taken from it the parts that work well and I’ve tweaked other parts, and I’ve added things too,” she says. “Like, Mel talks about soil building with the addition of compost but he doesn’t talk about cover cropping. And so I’ve gone ahead and planted green manure cover crops.

“This is rye,” she points out. “I’ll chop it down and till it back into the soil. But I also use it as a straw to protect and keep moisture in other squares that have seeds in them so they don’t dry out.”

Van der Fluit often has up to 100 squares going in her garden.

“For me, square-foot gardening has made life simpler,” van der Fluit says. “An example: When my lettuces are done doing their thing at the end of spring, I’ll take them out of their boxes, build up the soil and plant a different crop without having to rip everything out.

“That’s the really cool thing about square-foot gardening,” she says. “The crops can be planted and mature and be harvested at their own pace.”