Category Archives: Climate change

Zones in the Santa Cruz Mountains

Seems like I "Google" something nearly everyday. I can barely remember what life was like before the information highway. For subjects like gardening however information from your own neck of the woods is the best. Locals have knowledge of weather patterns, plant behavior, pests and diseases, flowering sequences- you name it – there's a neighbor or friend or local expert who can help you. I'm fortunate in that lots of people ask questions of The Mountain Gardener about gardening here in our unique part of planet earth. Here are some recent inquiries. You might be wondering about the same things.kale covered with frost

We all rely on Sunset's Western Garden Book as the bible for gardeners. With each new edition I eagerly look to see if they've figured out that Felton is not in zone 7. Sure it was pretty cold around here in January but even with climate change the San Lorenzo and Scotts Valleys are not as cold as a zone 7. Even considering microclimates we can grow a wide variety of plants that would not survive in the Sierra foothills, the Gabilan range, the Coast range or other zone 7 areas. Wish they would ask local nurseries and knowledgeable horticulturists what the weather is really like here.

Knowing the climate in your area helps determine what you can grow in your garden.  It's confusing to both new and seasoned gardeners alike. Here are some tips to help you determine in what zone you garden.

Zone 7 has the coldest winters in our area.  Very high ridge tops like the Summit area and the most northern portions of Bonny Doon lie in this zone.  My records show average winter lows ranging from 15-25 degrees based on 20 years of input from gardeners in these areas.  This does not apply to other areas of zone 7, just those around here.   Record lows have occurred during freezes in 1990, 1996 and 2007 but as gardeners we rely on average highs and lows to help guide our planting times.  Spring weather comes later in this zone with the growing season mainly from April – October.

Zone 15 encompasses most of our area.  Winter lows average 20-30 degrees. The valley floor of both San Lorenzo and Scotts Valley lie in this zone and are what I call "a cold 15".  Cold air sinks and is trapped in these areas. Often there is damage to the tips of oleanders and citrus while gardenias and tropical hibiscus need a lot of extra protection.There are warmer parts of this zone, though, where the growing season starts in March and ends in November.  These areas rarely get a freeze after March 15th or before Thanksgiving.

Zone 16 – those who live up off the valley floor but below ridge tops live in this "banana belt". Pasatiempo also falls in this thermal zone.  Light frost can occur during the winter but mostly the winter lows in this zone stay near or above freezing. You might have cold pockets on your property however so plan accordingly.

Some gardening tasks are dependent on the weather. Many shrubs,perennials and grasses are to be pruned after danger of frost is past and many vegetables should be started after this time as well. As a reminder the estimated date of our last hard frost is March 15th. I've kept a weather journal for my area, the San Lorenzo valley, since 1992.  Based on my records, we may get a few frosts, especially after a storm, in late March or early April but for the most part, we have mostly passed the chance of having a heavy frost. Still it's a good idea to have a cardboard box or blanket ready to protect your young seedlings.

I hope this helps in choosing plants that will thrive in your garden.
 

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.