Design trends

Green Isn’t Just for St. Patrick’s Day

Choiya ternata ‘Sundance’ sports lovely chartreuse green foliage

Wearing something green on St. Patrick’s Day has been a tradition since immigrants, particularly in the United States, transformed the holiday into a largely secular event celebrating all things Irish. Cities with large numbers of Irish immigrants staged parades going back to 1737 in Boston and in New York City since 1762. Although blue was the color traditionally associated with St. Patrick, green is now commonly connected to this holiday with shamrocks high on the list of things to wear on this day.

On Thursday, March 20th at 2:01am the day and night will be almost equal. That’s why it’s called the Spring or Vernal Equinox. Some years it falls on March 19th. It would occur on the same day every year if the Earth took exactly 365 days to make a complete revolution around the Sun. But it actually takes the Earth 365.25 days on average to go around the Sun once. Whatever the exact date and time it’s spring and with St. Patrick’s Day also in a few days I plan to add something green to my garden and tick off a few tasks on my to-do list.

There are endless shades of green in nature because color is dependent on light. Humans can see more shades of green than any other color. This is an evolutionary trait handed down from our ancestors who needed to differentiate the shades of green in order to know which plants to eat and which to avoid. Everywhere you look, it’s green- forest green, apple green, olive green, fern green, sage green, chartreuse green. Even all those showy flowering trees blooming now will soon be sporting bright green leaves.

I often get a request for green to be in the color palette of plants that go into a garden. There are green flowers that you can grow and of course, many shades of green foliage. The low wavelength of green promotes calm, relaxation and restfulness.

Diamond Heights ceanothus is a lovely groundcover and doesn’t require much irrigation.

One of my favorite groundcovers for sunny areas that looks beautiful as it fills in between other low water use plants is Diamond Heights ceanothus. Carpet an area with this dense, low mat of golden yellow and lime-green variegated foliage. It looks great year round. The pretty light blue spring flowers take second place to the leaves.

This is one of those versatile plants, performing just as well in dry soils and tough situations as it does in sheltered gardens with partial shade and rich soils. If you want a spectacular effect, plant it as a group. Each plant covers 3-5 ft. Because the foliage makes a cover that weeds seldom manage to penetrate, it’s a real maintenance saver. Use it on difficult sites such as banks as well as in garden beds and raised beds. It’s also a stunner as a container plant, the foliage spreading wide on all sides.

Leucadendron Safari Goldstrike

Another great greenish flowering shrub to try is Safari Goldstrike Conebush. This leucadendron is a vigorous compact grower to 6 feet tall and blooms during the winter and spring. Its bracts are excellent as a cut flower and foliage harvesting. They grow in full sun and have low water needs.

Some of my favorite plants that have green flowers or shades of green foliage are green hydrangeas, green hellebores, lime green coral bells, Lady’s mantle, Sum & Substance hosta, fatsia japonica, green gladiolas, Mediterranean spurge and Bell of Ireland, of course

Design trends

Long-Lived Survivors in the Garden

One of the earliest, easy-to-grow, spring blooming shrubs in our area.

Many, many years ago my landscape designer group was fortunate to get a private tour by the head gardener at Filoli Gardens. One of the takeaways from this informative afternoon was the plants that have survived there since the early 1900’s without any care. They are true survivors.
Growing in out of the way places in the over 600 acres of Filoli are plants that you see blooming around here right now.

Old fashioned shrubs like flowering quince and forsythia figure prominently in many old gardens because they are tough plants able to survive neglect and still look beautiful. The bare stems of forsythia are completely covered with deep golden-yellow flowers in late winter and early spring and become the focal point of the landscape when in full bloom. The showy stems of this easy-care shrub are great for cutting. Forsythias are native to eastern Asia but a chance discovery in Germany by a grower who specialized in breeding for the cut flower industry led to the especially vivid variety ‘Kolgold’ in the 1800’s. Forsythia has long been used in Chinese medicine. The flower petals contain powerful bacteria-fighting properties which make it an important dressing.

Flowering quince is another old garden staple providing early color. They are easy to care for and nearly indestructible in almost any soil that is well drained and not overly fertile. Once established quince is a very drought tolerant plant and their spiny branches make them an excellent choice for hedges, screening or as a security barrier. There are red, pink, orange and white flowering varieties. The Toyo Nishiki cultivar even has pink, white and solid red flowers all on the same branch.

Recently while reviewing plant preferences with a client they mentioned that spirea has done very well in their poor draining soil. I haven’t thought about this workhorse plant in quite a while. They’re not “trending”, but they are good, love-lived, easy-to-grown beautiful shrubs that deserve a second look.

Spirea japonica is drought tolerant once established. Bunnies and deer don’t like them and they are not invasive in our area. Blooming for a very long time they attract pollinators and can control erosion. Several varieties are grown and available including the classic ‘Antony Waterer’. Other popular varieties include Double Play Gold, improved form of ‘Goldmound’ and ‘Goldflame’. The brighter yellow foliages covers a more compact shrub and it blooms profusely with hot pink flowers from early to late summer.

Another early flowering plants that is easy to grow in the shade is Clivia or Kaffir Lily. Buds are just starting to form on mine. Every year I look forward to their huge flower clusters that emerge between dark green, strappy leaves. Even in dark shade they will bloom and brighten the late winter/early spring garden although they would do fine in morning sun. If you have a north facing window you can grow them as houseplants. Clivias are hardy to several degrees below freezing. Clivia bloom best when crowded.

Design trends

Plants for the Allergy Sufferer

Flowering dogwood is a good tree to plant is you have allergies.

I live on Boulder Creek where the native red alder is in full bloom. Their catkins release wind-borne pollen which along with the redwoods wreak havoc with my friends with seasonal allergies. According to Pollen.com the allergy alert today is medium high at 7.4. It’s going to be a bad day for them.

It’s the mating season for redwoods. Redwood pollen is dispersed by the wind. Strong winds blow the yellow redwood “flowers”, which are actually the flowers of the male cone, to release their pollen. Unfortunately because redwoods live in such a narrow band of coast line, there is no allergy shot for those highly affected by them. Pollen.com predicts pollen levels will increase as alder, juniper and birch release their pollen. Then come the oaks and sycamores.

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.

Yes, 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.

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.

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 for 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.

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 sneeze-less 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.

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