Category Archives: Climate change

Saving Water in the Garden

With so much rain this winter it's easy to forget just how precious water is. Globally, water is the new oil. In our own Santa Margarita aquifer everything we can do to replenish the groundwater is vital for our own survival and for that of generations to come. Water cost money – to buy, store, collect, pump, filter and distribute. It just makes good sense to be water wise in your home and garden.

Scotts Valley Water District has been offering a free information series during January about water conservation. Each Wednesday night from 7:00-8:30 a different subject is presented. They are open to the public. I've attended two so far- Storm Water Management and Rainwater & Greywater Harvesting, lots valuable information about ways to save water and money.

When it rains it pours. Think about ways to slow this free water from the sky and prevent it from running off your property. Allow it to spread and sink into the ground. Easy ways to do this can also make for a beautiful landscape.

Design your patio using permeable pavers that allow storm water to percolate into the soil. Whether you choose flagstone over a gravel base, pervious concrete, interlocking pavers with spaces between or crushed gravel all enable rainwater to seep into the soil, recharge the aquifer and prevent runoff into streams and storm drains.

Pervious pavement for driveways can capture runoff , recharge the groundwater and keep pollutants in place in the soil. Large volumes of runoff causes serious erosion and siltation in rivers and streams. Naturally occurring micro-organisms digest car oils, leaving little but carbon dioxide and water. Turf block (concrete blocks with holes) is a good choice for areas that don't receive a lot of heavy traffic and can also be used for paths with gravel or groundcover between.

Plants and trees also slow water runoff. They help stabilize slopes and prevent erosion of valuable nutrient-rich topsoil. They create wildlife habitat and act as a natural pest control. A beautifully designed landscape using California native or drought tolerant plants reduces the need for fertilizers, pesticides, excessive watering and overall maintenance requirements.

You can design a rain garden to capture stormwater runoff from roofs, driveways and other impervious surfaces and allow the water to sink back into the ground. A dry creek bed can also be a good way to slow runoff. Some utilize drain pipe underneath to capture the rainwater so it has time to percolate into the ground.

Using vegetation or mulches to cover bare soil is a key ingredient to slow down runoff. Mulches are a good choice for areas with less than 33% slope, Vegetation works well on areas with less than a 50% slope. Mulch can be organic-such bark chips, straw or grass clippings or inorganic gravel or cobbles. All protect soil from erosion, conserve soil moisture and prevent weed growth. It's all part of the plan to slow, spread and sink water back into the ground.

Installing a rain barrel is a simple way to catch rainwater runoff from your roof. If you have room you might consider a large water tank above or below the ground to collect water. A friend of mine operates a small nursery on her Watsonville property. Sherry and her husband, John, decided to collect the rainwater runoff into a series of tanks to save money and utilize this resource. The 4500 sq.ft roof of their barn provides enough water to fill 3 large tanks. Last year they collected enough water to irrigate their nursery, Terra Sole, for quite a bit of the year. They eventually plan to install solar panels to offset the energy required to pump the water. Every little bit helps

If you'd like more information and ideas about how to beautify your landscape and save water, maintenance costs and time  please come to the last Water Wednesday presentation by Scotts Valley Water District on Jan 30th at 7:00 pm at their office on Civic Center Drive. LeAnne, the water conservation coordinator, and I will be showing slides of landscapes, some of which I designed, that feature low water use plants, lawn replacement ideas and California natives. There's a solution for every family and lifestyle.
 

Quaking Aspen in California’s Eastern Sierra

On the eastern side of the Sierra, ribbons of brilliant gold flow down the mountainside. The color can be seen from miles away.  Meadows spread wide covered with vivid yellow-leafed Aspen quaking in a fall breeze. It's the height of the fall foliage season in this part of California.

As I drove down Hwy 89 south of Lake Tahoe past Markleeville and then over Monitor Pass to Hwy 395 each stand of aspen seemed to glow brighter than the last. I wondered if they would be as beautiful for future generations or if our impact on the environment would cause these glorious trees to change in any way.

Quaking aspen (Populua tremuloides) is the most widespread tree species in North America. It provides food for foraging animals and habitat for wildlife. It also acts as a fuel break and retains much more water in the environment than do most conifer species.

High mountain systems, such as the Sierra Nevada, are uniquely sensitive to anticipated global climate changes and act as canaries in the coal mine to provide early signals of significant climate-driven changes. Research in the Sierra Nevada by Pacific Southwest Research Station, which is a USDA Forest Service research organization, shows how vegetation has responded to climate in the past and indicates changes than 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 these 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 valuable in providing moisture in the landscape and habitat and food for wildlife. They are vulnerable in the face of global warming and climate change. Hopefully, we will not lose this wonderful tree in California.

If you're from a part of the country where these trees are native and you miss their fall color there is a new cultivar of Improved Quaking Aspen developed for mild winter areas like ours. It provides a splash of color for areas that are naturally moist like a natural stream or a high water table. They grow 20-30 feet tall and 15 feet wide and spread by underground roots to form a stand.

Good Shrubs for Erosion Control in the Santa Cruz Mtns

You know fall is just around the corner when you hear thunder. Seems like summer just started but now plants like lilac, rhododendron and dogwood have already set flower buds for next year. We don't know exactly what winter will bring. Will we receive lots of rain or a meager amount?

The latest from the Climate Prediction Center for the San Francisco Bay Area 2012-13 rainy season is that a mild El Nino event may be setting up. There has been a  weakening of the positive sea surface temperature in the Pacific. El Nino has been known to come with plenty of rain for our area. We are still in a wait and watch mode.

Long range outlooks for the fall from the CPC run from equal chances for above or below normal rainfall to a slight tendency toward below normal. For the November through January period the probabilities start to shift and a slight chance of above normal rainfall creeps up along the coast from the south.  By the time we get to the December through February period, the outlook is for above normal precipitation for the whole state with significant above normal chances for the Bay Area.

This is not a forecast but an outlook for the probabilities of above or below normal precipitation. If we do get heavy rains in January or February you should be prepared. Do you have a slope that might have an erosion problem?  Now is the time to start planning and planting. The nights are cooler, the days shorter, the soil still warm. Everything that a new plant needs to get a good start.

What plants are good for controlling erosion in our area? When choosing plants to cover a bank for erosion control, assess the conditions of the area you want to plant.  Is it in the sun or shade?  Is it a naturally moist area or dry?  Do you intend to water it or go with our natural cycle of wet in the winter and dry in the summer? Matching the plant to the site conditions will ensure success.

When designing a plant layout I consider whether I want a sweep of the same plant or a tapestry effect with a variety of plants.  Using more than one type of plant allows me to work with contrasting foliage adding pattern to my composition.  To create a stunning combination choose 5 or 6 styles and repeat them in small drifts to carry the eye through the composition. Add grasses for linear texture.

If the area you need to stabilize is large and mostly shade, consider Ribes viburnifolium aka Evergreen Currant which grows 3-6 ft tall spreading to 12 ft wide. It needs no irrigation when established. Another plant that tolerates shade and needs no irrigation after 3 years is Mahonia repens aka Creeping Mahonia. It grows 1 ft tall by 3 feet wide spreading by underground stems that stabilize the soil.

Symphoricarpos aka Common Snowberry or Creeping Snowberry can hold the soil on steep banks. They tolerate poor soil, lower light and general neglect. Philadelphus lewisii aka Wild Mock Orange tolerates some aridity and partial shade. This beautiful, fountain shaped, fragrant flowering shrub grows about 8 ft tall by 8 ft wide and is not fussy about soil.

A bank in the sun would contain a different plant palette. Some of my favorite plants to control erosion in this situation include Ceanothus in all its forms. Groundcover types like Centennial, Anchor Bay and Maritimus are not attractive to deer like the larger leaved varieties. Rockrose such as Cistus purpureus also provide large-scale cover for expansive sunny areas.  Their dense strong root systems helps prevent soil erosion. Choose from white, pink or magenta flowers on plants varying from 1-5 ft. high depending on which variety you choose. This Mediterranean native is fast growing, drought tolerant and deer resistant.

Smaller plants for color that control erosion are lavender, California buckwheat, salvia leucophylla, California fuchsia, deer grass, needle grass, mimulus, yarrow, Pacific Coast iris, bush poppy, penstemon and artemisia.

These suggestions are just a few of the plants that control erosion. Every area is different and every situation unique. Email me if you would like help with your area.
 

Gardening in Snow in the Pacific Northwest

It was a snowy afternoon in the Seattle area when I attempted to ferry across the Puget Sound to Whidbey Island. Whiteout conditions got the best of us so we chickened out and decided instead to go to a local arboretum and the garden of one of my sister’s friends. While the snow came down this is what I learned about local gardening in the Pacific Northwest.

This is the home of Lily-of-the-Valley shrub and heather which are blooming now.  Crocus, Siberian iris and narcissus poked valiantly through the snow. Ornamental grasses, not yet cut back, made me think of the prairie in winter. Japanese maples of every type showed off their exquisite form cloaked with a few inches of snow.  Everywhere tall evergreen trees as well as dwarf forms anchored the landscape especially in winter.

The owner of this garden turned a weedy easement that stretched along the entire back fence line into curved planting beds created from retaining walls of beautiful dry stacked local stone. Many low water use evergreen and deciduous shrubs help this gardener in the summertime.  The Japanese maple marks where a utility pole once stood. Snow covered many of the plantings but I can just picture how pretty the spirea and viburnums will be when they bloom in spring.

We grow many of the same shrubs in our gardens as I saw in the Pacific Northwest.  Water conservation is important here, too. Although this area receives lots of winter rain and snow in the mountains by summer’s end, rivers and reservoirs in the Cascades, ground water levels and collected snowmelt reserves are gone. A little rain falls in the summer but it’s still a Mediterranean climate here. Water needs of people compete with those of migrating salmon and other wildlife and vegetation. Climatologists are predicting that climate change may mean less snow pack in the future.

Color in the wintertime is priceless even if it isn’t snowing. It’s too early for the flowering cherries but a few of the plums were starting to show color. Hellebores of every color combination imaginable were blooming in most gardens although the snow weighted down the foliage. Their  flowers stood stiffly upright like the the guards at Buckingham Palace. Bergenia flower clusters braved the weather, too. Some of our common shrubs like ceanothus, abelia, barberry, mahonia, sarcoccoca, hebe, choisya, rockrose and osmanthus are also grown here.

Later, at the in the Emerald City I was treated to fabulous gardens designed using found materials, water catchment techniques, unique paving materials and slope stabilization ideas. One large display garden featured a high mountain forest setting, complete with massive waterfall and huge boulders. A 20 foot tall Japanese maple over a 100 years old dominated one corner. They like things big in this part of the country.

Another favorite garden at the show had us wishing we could transport the whole scene to our own homes. Vintage galvanized pails and wooden flats atop repurposed shelves in a shed with windows created a cozy scene surrounded by roses growing on old wood and wire fencing. Guess you had to be there to experience it’s charm.

As I write this, snow is being forecast for our own area. Maybe it’s following me. I enjoyed my trip to the Pacific Northwest and came back with lots of new ideas but there’s no place like home.