Savvy Gardeners Can Wring Pleasure From Valley’s Clay

Gardening in the San Fernando Valley is different than in other parts of Los Angeles, landscaper and gardener Nancy Harrington said.

Valley soil tends to be harder, temperature swings are wider and the air is drier than in coastal areas of Los Angeles. And, she said, all of that is good for some plants and not so good for others.

Take, for example, the impatiens. The plants with the pretty pink, white or red small flowers will grow in the full sun in Santa Monica, but should be moved to the shade in the Valley, where temperatures are hotter and the air is drier, Harrington said.

Flowers that do well in the Valley are coral bells, which are native to California, and durable, dependable violets, Harrington said. Plants that do not do as well are ones that require a coastal influence, such as stephanotis and mandevilla vine.

Hard, Compact Clay

The curse of most Valley gardeners, says Harrington, is the soil.

“It’s hard, compact clay soil,” said Harrington, who operates Evergreen Garden Design and Maintenance out of her home in Canoga Park and teaches gardening classes at The Learning Tree, an adult education school in Chatsworth.

“In some parts of Canoga Park, it’s like digging in concrete,” she said. Other parts of the Valley, such as North Hollywood, have better soil.

For those with the hard stuff, Harrington recommends working in soil amendments--composted organic matter. This aerates the soil so that plants have room to grow and also provides nutrients.

In her own yard, Harrington can reach into the ground with her fingers, and the soil is still loosely textured and flaky even several inches beneath the surface.

“This is how all gardens should look,” she said.

Deep Watering

Besides preparing the soil, watering properly also is important.

“Watering has to be done thoroughly to get down deep,” she said. “Because our soil is so compacted, water puddles quickly and you think you’ve watered enough. But it hasn’t penetrated deeply. Turn off the water, wait a while and water again.”

Valley gardeners also must be aware of the problems cold or hot weather can cause.

“Cold weather is more of a problem than hot,” Harrington said. She said many of the plants in the Valley are native to subtropical areas and thus tolerate the cold poorly, especially when there is little rain.

In particular, Harrington said, there are cold pockets in Woodland Hills and Reseda. This year, for example, temperatures went below freezing several times during January and February. New plantings of hibiscus and bougainvillea were hard hit while older, established plants survived without damage, she said.

Summer heat can be compensated for with extra watering. “But heat and wind is the worst,” she said. The combination can cause a plant to transpire water at a rate that is too rapid for it to survive, even when well watered.

Despite--or sometimes because of--the wider temperature ranges in the Valley than in cooler parts of Los Angeles, many plants do better in the Valley, Harrington said.

“Crape myrtle, one of my favorites, can really mildew over the hill but it is very happy here,” she said, noting that the coastal fogs burn off more slowly than fogs in the Valley. “Fruit trees do better here because the chill helps them to bear fruit.”

Harrington’s yard is filled with pointers and ideas for other gardeners. The lawn of her rented house at first was a browned Bermuda and weed mix. She began fertilizing, watering and seeding with fescue, a type of grass, to restore the lawn.

“Putting in a sod lawn could have cost $3,000 and that could be put to better use other ways in the yard,” she said.

Her driveway, which strongly reflects the sun, is lined with a collection of well-tended succulents.

“Because of the extreme glare, nothing else would grow here and it would be useless to try,” she said.

Alternative to Removal

Instead of attempting the almost impossible task of removing a jungle of old ivy on a trellis, Harrington pruned away the foliage on the bottom four feet, leaving the old trunks bare and the leaves concentrated on the top two feet to form a decorative border. The newly exposed, gnarled trunks have a striking sculptural effect.

Harrington, a pragmatist when it comes to gardening, advises clients when to give up the dream of planting a dark shady corner. “I know what you’re picturing but nothing will grow here,” she told one client. And she rejects the fruitless mulberry tree with its invasive root system as more trouble than it is worth.

She readily acknowledges that many plant selections are trial-and-error, even for most professionals.

When it comes to buying plants, snapdragons for example, she will buy the plant covered with buds rather than one already in full bloom. For one thing, plants that are transplanted during the budding stage will adapt more quickly to their new environment, she said.

Look at Other Yards

Harrington cautioned home gardeners to bear in mind the eventual size of plants. She suggested driving around neighborhoods that are already grown in to see how big plants get.

“Front yards are all public domain in a way,” Harrington said.

Such drive-bys are also rich in landscaping ideas, such as which plants thrive on what side of a house and what plants look good planted together, she said.

“Everyone loves flower gardens but the general rule of thumb is: the more color, the more work. Also, the faster-growing plants require more work,” she said.

She said slopes are the hardest to maintain. “They require a lot of patience,” she said. “The water runs off and there’s always concern for erosion. The biggest mistake people make here is depending solely on a ground cover to do the job. If you look at slopes in nature, you’ll see trees, shrubs and ground cover.” She suggested that home gardeners follow nature by planting trees because their roots hold up the soil.

“Ground covers are more of a finishing touch than a solution,” she said. “Some ice plants are so heavy they can pull the ground down.”

Class Project

Harrington has been teaching gardening techniques at The Learning Tree for more than a year. Every quarter she offers an eight-session class that includes lectures on soil preparation, watering and pruning. Students visit a local nursery on a field trip and end the class by planting a yard together.

Harrington studied ornamental horticulture at Pierce College and also took classes at UCLA Extension’s landscape architecture program. While still in school, she decided to start a garden maintenance business.

Harrington, who is thin and about five feet tall, said clients are surprised to see a tiny woman show up to do their gardening. However, she has found that being a woman is an advantage because many of her clients are women. Although she now hires a man to do some of the harder chores, she has done the hard, physical work of routine gardening.

“Digging is the hardest,” she said. “The soil here is the worst.”