SUSTAINABLE GARDENING AT THE FAIR

Of the many ways that we look at gardening -- hobby, exercise, passion for

plants, source of fresh produce, landscape filler -- the number of us in

Sonoma County who consider it a way of life is essentially a small segment of

the population. But those that do have joined a growing group worldwide who

support sustainable gardens, gardens that work in harmony with nature and

maintain long-term health by recycling nutrients back into the soil, relying

on beneficial insects and organic supplements, and adapting to the climate in

which they are planted.

To really get hold of the concept, it helps to ask the question: How does

nature sustain a garden? Certainly not with elaborate irrigation systems, bags

of petrochemicals, and pesticide sprays.

Answering the question and lessening negative impacts on the environment in

our own communities and even on a global scale may at first seem difficult,

but there's a lot of help all around.

One of the most entertaining learning tools appears every year at this time

at the Sonoma County Fair in the Hall of Flowers.

Just a few steps away from the splash and splendor of the fanciful

exhibits, out on the sun-lit patio, Sonoma County Master Gardeners set up an

educational display co-sponsored by the city of Santa Rosa. Their garden is

one of the most visited of the smaller exhibits because they cater to the

everyday needs and interests of local gardeners. Their plants are labeled and

are chosen for suitability for our climate.

This year, their design highlights various elements of a sustainable garden

that extends beyond planting beds to include a home and its entire lot.

Focus on water

As you might imagine, managing water is a key element in a sustainable

garden. Beds are set up to accommodate drip irrigation lines so that plants

receive water slowly and directly to the root zone. Little moisture is lost to

evaporation and none to runoff.

Permeable surfaces are just as important. Instead of solid concrete that

lies in front of so many home garages, reflecting heat onto dwellings and

sending rainwater down the gutter, the driveway in this exhibit is permeable.

It is constructed out of open-faced concrete blocks interplanted with a low

ground cover. Such a design allows rainwater to filter into the soil and

restore supplies in underground aquifers.

The ''green'' planted house roof serves a similar function. A green roof

also slows water movement during rainy weather and in summer has the advantage

of reducing heat indoors. More common in cities--and required in much new

construction--one of the most renowned green roofs is on Chicago's City Hall.

An excellent Web site, www.greenroofs.ca, has an illustration of the

components of a green roof and lists many resources related to such a

structure described therein as ''an extension of the existing roof, which

involves a high quality water proofing and root repellant system, a drainage

system, filter cloth, a lightweight growing medium and plants.'' Other types

of permeable surfaces that allow water to move underground are decks instead

of solid concrete patios, pavers and gravel instead of solid walkways, and dry

creek beds. This demonstration garden doesn't have space to show all of these

features of course, but there are enough to stimulate thought and urge us to

action.

Landscape plants

As this green garden shows, plant diversity is an important element in

maintaining garden health. Here edible and ornamental plants are combined in a

front-yard landscape. There is nothing wrong and everything right about

intermingling an artichoke or green peppers with perennials and ornamental

shrubs. Parsley and ferny carrot tops are just as attractive as a good many

flowering annuals. And by letting one or two of the latter go to seed, we can

attract beneficial insects with their blossoms.

The side fence in the demo garden functions as a support for grapes and the

tree in the front yard is a lemon, but could easily be a Washington navel

orange. Both provide fruit for months. If you prefer a tree with somewhat

different features, consider a Japanese persimmon (Diospyros kaki). Few trees

are more brilliantly colored and picturesque in autumn than persimmon.

If you're saddled with a chain link fence in your front yard, try using it

as a trellis for edibles. Grapes, cucumbers, summer squash, peas, and beans

all need support and thrive in full sun that fills most street sides.

Herbs also fit easily into front yards. Lemon verbena (Aloysia triphylla)

is a wispy, fragrant shrub that requires little water, as do rosemary

(Rosmarinus), lavender cotton (Santolina), sages (Salvia) and thymes of all

types.

Recycling

Compost and vermicompost are the center of recycling efforts in a

sustainable garden, and both are well demonstrated in the Master Gardener

exhibit. Kids who may be bored looking at gardens always find it intriguing to

examine activity in a worm box.

Volunteers will be on hand to answer how-to questions and hand out

literature, not only on composting but also on all topics relating to home

horticulture, particularly sustainable gardening and pest reduction.

.

Rosemary McCreary, a Sonoma County gardener, gardening teacher and author,

writes the weekly Homegrown column for The Press Democrat. Write to her at

P.O. Box 910, Santa Rosa, 95402; or send fax to 521-5343.