A different take on gardening

Jennifer K Mahal

Sitting at a table in Mariners Park, Douglas Kent looks around at

the trees, shrubs and grass. It’s pretty, he says, but if the city

was concerned with the environment, they’d pave it with concrete.

No, Kent is not a developer. He’s not against open space. The

Costa Mesa man is a gardener whose controversial new book “A New Era

For Gardening” espouses the theory that many gardens -- through both

the plants and their care -- create more carbon dioxide than they do

oxygen.

The oxygen plants that release into the atmosphere during their

lifetime, says Kent, is sucked back when the biomass (dry organic

matter) of the plants is composted. That essentially makes plants

oxygen neutral. When you add in all the carbon dioxide created by

gardening -- from the chemical fertilizers to the gasoline used by

lawnmowers -- it means gardens are contributing to global warming,

Kent theorizes.

The only way to gain some of that oxygen back is to not compost

all of the plant material and instead to bury it in a landfill, he

says. That way the release of carbon dioxide during decomposition is

contained. It is not that Kent is anti-composting, it’s just that he

thinks that we do too much of it.

“Compost is the cheapest, most versatile, most effective material

for a landscape,” Kent says. “But you hit a diminishing return

point.”

Watching two children climb a tree, Kent says the carbon dioxide

costs of Mariners Park can be justified. After all, it’s an area that

gets used by many people. It’s the front lawns, back yards and small

strips of grass that concern him more.

“If we can just start out with small parts, it could lead to a

whole that’s beneficial,” he says.

“A New Era for Gardening” provides suggestions for how to increase

the oxygen production in gardens. Using native plants, replacing

mature plants, mulching only 10% of a landscape’s green waste and

avoiding “fleshy” plants that are water and nutrient dependent are

some of the steps advocated.

The book, which includes a way for people with green thumbs to

audit the oxygen and carbon dioxide production of their gardens, has

generated Kent some hate mail since it was released in the Midwest

and Canada.

Though it’s based on basic scientific principles, it’s a hard

theory for people to accept, he says.

“I think of myself as an environmentalist,” said Charlotte

Marshal, a member of the board of directors of the Manhattan Beach

Botanical Garden who edited the 103-page book. “I grew up in the

‘60s, was there for the first Earth Day, I try to believe I put into

practice things to make the Earth a better place to live.

“When Doug brought this to me, it went against things I thought I

knew.”

Marshall is now working with Kent on an oxygen audit of the

botanical garden. Some of the other board members were hesitant at

first, she said, but then decided that they wanted to know if the

garden is helping or hurting the environment.

Kent has been involved in gardening since he was a teenager. His

first experiences were “punishment for being an errant child.” Kent’s

parents would send the 14-year-old boy to his great aunt and uncle’s

home in Corona del Mar to work in her quarter-acre landscape of

flowers.

“She nurtured a love of gardening in me,” he says of his great

aunt, “and it stuck.”

Kent attended Orange Coast College, then Cal Poly San Luis Obispo

before graduating Cal State Long Beach with a bachelor’s in

sociology, emphasis in environmental policy. For years, he worked at

Roger’s Gardens in Corona del Mar, running an environmental lecture

series.

His first taste of environmentalism came through the Environmental

Nature Center in Newport Beach. At 21, Kent wrote “A Field Guide to

California Natives,” which is still used in an updated form by the

center.

He got the idea for “A New Era of Gardening” after reading

Irvine’s development plan for sustainability, which was written in

the late 1980s. The numbers, he says, did not add up. So, he started

doing research on oxygen and carbon dioxide production.

In the meantime, Kent developed a resume that included working

with FireSafe Marin as a horticultural advisor, becoming a garden

columnist for San Francisco Bay Area newspapers and writing a

well-received book on landscaping for fire prevention.

He finished “A New Era of Gardening” in 2001.

“I would encourage people who might initially think he’s all wet

or way off base with his theory to just read the book, go all the way

through and then just think about it,” Marshal says.

“A New Era for Gardening” is not yet available in local

bookstores, but it can be ordered through www.gardeningforoxygen.com.