Category Archives: Design trends

Design trends

Gardens Change with Time

Whether you want them to or not all gardens change with time. It?s part of nature that the fittest survive. Possibly you have different ideas of what you want your garden to look like but it?s hard to fool Mother Nature. Several years ago I had the opportunity to visit a special garden in the Gilroy area that has evolved with time. This garden of California native plants truly demonstrates how nature can decide the best plants for birds, butterflies, wildlife and people.

It was one of those classic mild autumn days when several fellow landscape designer friends and I were treated to a tour by the enthusiastic owner of 14 acres of land. Located at the base of Mount Madonna the property is called Casa Dos Rios. Jean Myers, the owner, loves to share her property and especially the journey that has transformed it from a formal landscape with lots of lawn to the present truly native wild garden. She loves that the landscape now supports all sorts of wildlife including birds, mammals, reptiles, amphibians, insects and fish.

A few of the native plantings have been more successful than she would have liked. Jean laughed as she pointed out the California rose thicket that has taken over the entry garden. She wishes she had planted the native wood rose instead which doesn?t spread as much. Her new plan is to remove the wild rose to make room for other native plants that aren?t so aggressive.

At this time of year a native garden is at rest. There was a quietness to the landscape as the wind blew the grasses. Deer grass has naturalized in garage swaths. Originally, Jean planted many varieties of native grasses and some still remain but the deer grass have been particularly successful. Jean explained that this grass was used for making baskets by the Ohlone Indians that used to live in the area. To keep this grass fresh looking she cuts them back to 6 inches from the ground in late winter.

California aster are butterfly and pollinator magnets

The California aster was still blooming along the path as we made our way to the frog pond. This plant is well liked by the native moths and butterflies, Jean said, as it provides a late source of nectar. The lavender flowers make perfect landing pads. The two species of butterfly weed bloomed earlier in the season and had already spread their seed for next year.

The frog pond consists of basalt columns that drip water into a deep pool filled with rocks that cools the water in the heat of the summer. Jean said the area is usually alive with birds but they were keeping their distance during our visit. Lots of time for them to bathe later when we weren?t invading their space. She said Pacific tree frogs and Western toads call the area home, too.

This ground cover is fire wise native and has high quality nectar favored by hummingbirds

Another late blooming plant, the California fuchsia, covered a slope alongside massive granite boulders. You could barely see the foliage through the hundreds of flowers of this red blooming variety. These plants spread easily and with a bit of late winter pruning look great late into the season.

Native iris tolerates sandy, clay and serpentine soils and seasonal flooding

Jean loves all her native plants. From the butterfly garden to the bog garden she had a story to tell about each area. In the spring, Jean said, the native iris steal the show. She rounded up 600 of these from nurseries all over California when the garden was first planted. Grouping each type together she says was half the fun to keep the colors pure in each stand. I was amazed to see them in areas of full sun as well as part shade locations.

We picked late blackberries and raspberries as we walked around this amazing 14 acre property that benefits all wildlife. She is an avid birder and she and her husband manage two creeks, the Uvas and the Little Arthur that support hundreds more bird species, including bluebirds, swallows and owls. ?There?s so much for them to eat here.? said Myers. She lets nature feed and attract all the native wildlife that visits.

It was a privilege to listen to Jean share her enthusiasm for gardening with California natives that attract wildlife and conserve water. I left with my pockets filled with seeds from native wild grape and clematis so I was hoping to always have a bit of Casa Dos Rios in my own garden.

Design trends

Enriching the Soil with Cover Crops

Every drop of rain that hits bare soil is destructive. Over 3000 years ago the Chinese protected their soil from erosion and increased fertility by planting cover crops. Early Nile Valley inhabitants also practiced this method of agriculture as did first century Romans. Lupines were planted in poor soil when no animal manure was to be had. Planting a cover crop is another way to improve and retain your soil. One of these days winter rains will come so be ready.

A cover crop is really anything that covers the soil and protects it from rain, trapping nutrients and preventing them from leaching downward. Cover crops can increase the tilth of the soil. Quick germinating grasses easily loosen the top foot of soil with their root mass. Legumes have a tap root, a bio drill, that penetrates 30″ downward while alfalfa roots can grow even deeper.

Orin Martin of UCSC?s Alan Chadwick Garden shows the extensive root system of bell beans.

Cover crops like bell beans, vetch and fava beans are especially valuable as they increase nitrogen levels in the soil in two ways. Atmospheric nitrogen can be “fixed” and left in the soil to fertilize subsequent crops. This is in addition to the nitrogen left from the foliage of the legume. Growing a cover crop also increases beneficial soil bacteria.

Fava beans, when grown as a cover crop and tilled into the soil in spring, increases soil fertility.

Cover crops are called green manure when they are chopped up and turned into the soil in spring before going to seed. The planting of legumes like peas and beans can actually increase nutrients in your soil giving you a net gain which is needed to offset what you take out of the soil when you harvest fruits, vegetables and flowers.

Late September to the end of November is the best time to sow cover crops. You will need to irrigate lightly a couple times per week if it doesn’t rain. You can also wait to sow just before the rains start. Be careful about working overly wet soil, however, as you can ruin the structure of your soil.

Recent research now recommends planting a mixture of grasses and legumes. Annual cereal grasses such as oats, rye and barley germinated quickly to hold and shield the soil until the legumes take hold. Bell beans, fava beans and vetch, which are the best legumes for our area, grow slowly the first 3 months then take off growing 70-80% in the last 3 months. The ratio of grass seed to legumes can vary from 10% to 30%.

There are other legumes that fix nitrogen but nowhere near as efficiently as bell beans. Crimson clover seed is more expensive, needs lots of water to sprout and competes poorly with weeds. Mustard causes competition with the fruit trees as bees will concentrate on the mustard flowers instead of the fruit tree flowers.

You don?t need to use an inoculant on legume seed. Our soils have a native resident population of good bacteria that will break down the seed coat and encourage the plant roots to fix more nitrogen especially after cover cropping for a few years.

Work the soil lightly with a metal bow rake then broadcast 8-10 seeds per square foot. Weeds should be already cleared but this step doesn’t have to be perfect. Afterward the area should be raked again lightly 1-2 inches down and covered with 3-4 inches of straw. Wood chips would be fine, too. Mulch heavier if you have bird competition. Cover crops are vigorous and will come up through just about anything. Water in lightly.

If you plan to let your small vegetable garden lie fallow over the winter instead of planting it with a cover crop you can cover it with manure and straw and I?ll talk about that in another column.

Design trends

Fall Color & Climate Change

Although it?s a bit early around here to see fall colors it?s happening at the higher elevation. Or is it? Have the wildfires affected the changing of the leaves? And what about the effects of ongoing climate change? How is our planet changing?

Ebbet’s Pass

Quaking aspen (Populua tremuloides) is the most widespread tree species in North America. They generally grow in high altitude areas but also exist at sea level in places like the state of Washington along the Pacific coast where climate conditions are ideal. Quaking aspen provide food for foraging animals and habitat for wildlife. They also act as a fuel break retaining much more water in the environment than do most conifer species.

High mountain systems, such as the Sierra Nevada, are uniquely sensitive to global climate changes and act as “canaries in the coal mine” providing early signals of significant climate-driven changes. Research in the Sierra Nevada by Pacific Southwest Research Station, a USDA Forest Service research organization, shows how vegetation has responded to climate in the past and indicates changes that might be coming in the future over the next decade.

Climate has a profound influence in shaping our environment and natural resources. By looking at tree ring records of living and ancient wood and pollen lake sediments present, climate can be compared to historic patterns to show climate changes.

Research indicates a complex, unpredictable future for aspen in the West, where increased drought, ozone and insect outbreaks will compete with carbon dioxide fertilization and warmer soils with unknown cumulative effects. Aspen are vulnerable in the face of climate change. Hopefully, we will not lose this wonderful tree in California.

Weather conditions play a major part in the intensity of fall color. The time of year is nearly consistent but some years the show is more dramatic than others. The best conditions for intense leaf color to develop are dry sunny days followed by cool, but not freezing nights.

Recent wildfires have had an effect on changing leaf color. Not much had been studied in this field prior to the 2018 fires that ravaged our state. Researchers? measurements have shown that the total amount of sunlight available to a plant for photosynthesis decreased only slightly – about 4% – compared to the previous summer. The smoke didn?t block the light but scattered it. Direct sunlight might fall mainly on the upper foliage but diffuse light can reach greater number of leaves throughout the canopy. So smoke can have some affect on photosynthesis but not much more than a cloudy day. Oxidative stress levels can occur during expended smoke exposure, however, so for the health of your plants be sure to wash the leaves off after a smoky day.

Which plants put on the best show in our area? Here are some of my favorites.

California native Western redbud turns yellow or red in the fall if conditions allow. This plant is truly a four-season plant starting in spring with magenta flowers, then leafing out with apple green heart shaped leaves. Colorful seed pods give way to fall color. This small native tree or large shrub does well as a patio tree in gardens with good drainage.

Other native plants like spicebush and Western azalea turn yellow or gold in the fall. A native vine that lights up with the onset of autumn is Rogers Red California grape. If you have an arbor, wall or fence that needs covering quickly this is your plant. The green and gray leaves are transformed in autumn into great draperies of rich, scarlet leaves with clusters of summer fruit turning all shades of purple.

Edibles that turn color in the fall include blueberries, pomegranate and persimmons.

Trees and shrubs that do well in our area and provide fall color include Chinese flame tree, ginkgo, Idaho locust, Chinese pistache, crape myrtle, witch hazel, all maples, liquidambar, katsura, dogwood, locust, cherry, crabapple, oakleaf hydrangea, barberry and smoke tree.

More on our own fall color later.