Climate Zones

You know when you walk out the door how hot or cold it is, how windy, shady, moist or dry. You know if your soil is pure sand or hard clay because you?ve dug a few holes in your time. You don?t need a book to tell you these things. So why are the gardening zones described in Sunset Western Gardening book important when you add a new plant to your garden ? And why are they so confusing in our area?

Sunset Climate Zones for the Santa Cruz Mountains

We all rely on Sunset’s Western Garden Book as the bible for gardeners. With each new edition I look to see if they’ve figured out that Felton is not in zone 7. Sure Felton gets pretty cold 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 horticulturist what the weather and climate are 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 which zone you garden.

We really only garden in two zones around here – zone 15 and 16. The Sunset map erroneously shows Felton as being in zone 7. Based on my experience even ridge tops like the highest portions of Bonny Doon and the Summit area which gets an occasional dusting of snow fall mostly in a colder zone 15.

Zone 15 – this zone 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 zone 15. Cold air sinks and is trapped in these areas. There are warmer parts of this zone, though. 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”. 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.

Beside the zone you also need to note how much sun or shade you get during the growing season. There may also be microclimates on your property. Are you near the river in a canyon or gulch or up on a south facing slope? Some areas in your garden may be several degrees warmer than other spots such as up against a brick wall or at the top of a slope from where cold air drains. Planting a citrus at the top of a slope that drains away the cold will make your tree much happier than if planted in a low open area.

Soil quality is not taken into consideration in zone mapping. Since the soil houses the water and nutrient uptake system for most plants, it plays an important role. Most plant guides describe soil requirements in terms of well-drained, acid or alkaline, poorly drained or high organic matter.

If you have questions about which zone you are in, email me and I’d be happy to help. I hope this helps in choosing plants that will thrive in your garden.

Pollen & the Allergy sufferer

Contrary to popular belief acacia trees are not to blame for spring allergies

The acacia trees are in full bloom. Being one of the first flowering trees we see they get our attention. Blooming acacias are often blamed as the cause of allergic reactions at this time of year but acacias are largely pollinated by insects and their heavy pollen doesn’t tend to become airborne. It’s the non-showy, quiet plants you have to watch out for. If you?re an allergy sufferer some plants are worse than others for you.

About 25-30 popular landscape plants are responsible for the majority of plant-related allergies in California. During the height of the pollen season- from late February to June- there are often thousands of pollen grains in every cubic meter of air. One can breathe hundreds of them with every breath. Though pollens can travel many miles, the majority tend to stay in the general area of their origin.

Redwoods, oaks, alders, ashes and other wind pollinated trees like olives, birch, box elder, cypress, elm, juniper, maple, fruitless mulberry, pine, walnut, willow and privet are the major source of spring pollen. Most native plants are good in the sneezeless landscape but if you have bad allergies or asthma it best to avoid wind-pollinated ceanothus, elderberry and coffeeberry.

You may not be able to avoid those culprits growing on other properties but you can get the most out of your own backyard by creating a sneezeless landscape. Replacing existing plants may be impractical but planning future plantings with these things in mind will save you a lot of headaches down the road and let you enjoy the sunshine outside in your garden.

Flower type is a good way to judge plants. The best looking flowers usually cause allergy sufferers the fewest problems. Plants with bright, showy flowers are usually pollinated by insects, rather than by the wind. These flowers produce less pollen and their pollen is larger and heavier, sticking to the insect rather than becoming airborne and lead to sneezing, a runny nose and watery eyes.

Some trees that are good in anti-allergy gardens are apple, cherry, dogwood, magnolia, pear and plum. Shrubs like azaleas, boxwood, lilac, rose-of-Sharon, hydrangea and viburnum are also not likely to cause problems. Good flower choices include alyssum, begonia, clematis, columbine, bulbs like crocus, daffodil, hyacinth. Also good are dahlia, daisy, geranium, hosta, impatiens, iris, lily, pansy, petunia, phlox, roses, salvia, snapdragon, sunflower, verbena and zinnia. Lawns of perennial rye grass, blue grass and tall fescue blends are usually OK as they will not flower unless allowed to grow to 12 inches or higher. Bermuda grass, on the other hand, can pollinate when the lawn is very short, sometimes as quickly as a few days after mowing.

This year we?re not lacking for rain thankfully. Symptoms can become worse for the allergy sufferer if the body reacts to the disappearance of the pollen following its initial appearance only to have to have more of it later in the spring. According to Dr. Stanley Fineman, an allergist with the Atlanta Allergy and Asthma Clinic, “You become sensitized to it, so when you’re?re-exposed, you can get an even more violent allergic reaction.”

Here’s to a sneezeless spring for you allergy sufferers.

Tough Flowering Plants for Rain & Snow

It takes a pretty tough plant to flower in heavy rain let alone snow. How do they do it? After getting well over an inch of snow last week at my house up here in Bonny Doon all I know is I want more of these steel-clad plants in my garden.

Helleborus orientalis blooming in the snow

I garden in pretty tough conditions- light wise- not receiving sunlight for 6 months of the year. Still I have winter daphne, helleborus, abutilon, loropetalum. Autumnalis flowering cherry and choisya blooming now. The pansies, cyclamen and primroses are looking a bit beat up but they?ll bounce back. These are my winter flowering heroes.

After the snow melted I have to say the hellebore help up perfectly. I received a couple new ones last year for my birthday. Wish I had saved the tags. The double burgundy one is lovely. One of my favorites is called Cinnamon Snow but all of the varieties of this buttercup relative accept wind, rain, cold and less than perfect soil while getting by with only moderate watering in the shady summer garden. Deer aren?t attracted to them either

I had to wait a couple years for my variegated winter daphne to settle in before setting flowers but beginning last year it?s making up for lost time. There?s something special about a plant that will bloom in the depth of winter, hold up to rain and scent the garden all at the same time. With beautiful rosy-pink flower clusters and attractive yellow-margined variegated foliage, daphne make a great foundation plant for dappled shade gardens. They are deer resistant and have low water requirements during the summer. What?s not to love?

Another tough plant that can take weather extremes is the Lily-of-the-Valley shrub (Pieris japonica). There are many varieties of this early winter bloomer. Some have pure white flowers, other sport various shades of pink or dark rose. Mine is the smaller variegated foliage model with dainty, drooping clusters of pure white flowers in early spring. Right now it is covered with flower buds so dense that you?d think it was already blooming. The new growth in the spring has a beautiful pink tint. This shrub will hold up to the wildest weather. Another plus for the Lily-of-the-Valley shrub is that is useful for firescaping in the landscape and it isn?t on the menu for deer either.

Pink Australian fuchsia bloom profusely despite the rain, I added a variegated variety called Correa ?Wyn?s Wonder? to my own garden a couple years ago but I was cavalier about protecting it from gophers and alas it is not with me anymore. Still it?s a great plant. Although not related to hybrid fuchsias, the flowers are similar and their nectar feed the Anna?s hummingbirds when there?s not a lot of plants blooming for them. Australian fuchsia grow well in dry shade under oaks are deer resistant and drought tolerant.

I keep threatening to get a mahonia aquifolium. It would be perfect up here. They are a favorite of birds and indoor floral arrangers with cheery, bright yellow flower clusters that last for months. When each flower sets a purple berry they look like grape clusters. The edible berries make good jelly, too. There are 70 varieties of mahonia including our own native Oregon Grape which grows in the understory of Douglas fir forests. Mahonia aquifolium is resistant to summer drought, tolerates poor soil and doesn?t create a lot of leaf litter.

Other winter blooming plants include euryops, witch hazel, edgeworthia, michelia, grevillea and camellia, of course. Enjoy color in the garden regardless of what Mother Nature brings this winter.

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