Design trends

Plant Natives in the Fall

Pink flowering currant, like this Kind Edward Vii, are hummingbird magnets.

Every year I vow to add more California natives to my little garden. Problem is I don’t have much sun which is great on a hot day but not so great for plant growth. Sure there are lovely native plants that are tolerant of very low light conditions but not very many. Still I’m determined. So keeping this in mind this is the perfect time to plant California natives.

By planting from mid-September through mid-November, roots of all plants have a chance to grow during fall and most of the winter without having to supply nourishment to the leafy portion of the plant. Roots of deciduous plants still grow even after plants drop their foliage as long as the ground temperature is above 50 degrees. Cooler day and night temperatures slowly harden off the top of the plant to prepare for the cold days of winter.

Another reason that fall is the “no-fail” planting season is because plants put in the ground in fall need less water to establish. The plants themselves use less water since photosynthesis is slowed by shorter days even if it’s occasionally warm. Evaporation rates slow down also during fall so moisture in the soil lasts longer as well. Sometimes we get lucky with fall and winter rains perfectly spaced so the ground never completely dries out. Unfortunately this winter is predicted to be another La Nina but let’s hope we get more rain than last season.

Plants that thrive in dry, shady spots benefit especially from fall planting as they need established root systems before next years dry season. Dry shade sometimes occurs in places beyond the reach of the hose but also under native oaks. To protect the health of native oaks, it’s a requirement that plants underneath thrive with little or no summer irrigation.

Plants of proven success under these conditions include native currants and gooseberry. Red flowering currant is a show stopper capable of controlling erosion. In the spring, the long, flower clusters of this deciduous shrub will dominate your garden. There are many selections to choose from so if the huge white flowers appeal to you ‘White Icicle’ will be beautiful in your landscape. ‘Barrie Coate’ and ‘King Edward VII’ have spectacular deep red flower clusters and ‘’Spring Showers’’ has 8″ long pink ones. Grow in full sun to partial shade. This California native requires little water once established and is a valuable nectar source for hummingbirds.

Some other good California native shrubs for erosion control are western redbud, mountain mahogany, western mock orange, lemonade berry, toyon, snowberry, matilija poppy and western elderberry. Rbes viburnifolium, creeping mahonia, snowberry, ceanothus maritimus and ‘Anchor Bay’s are good groundcover selections.

Smaller natives that put down deep roots are heuchera, iris dougasiana, native grasses, yarrow, coast aster, California fuchsia, wild grape, mimulus, buckwheat, wild rose, sage and salvia.

Bush poppy (dendromecon rigid) is another native found right here in our area and needs no irrigation at all once established. Beautiful bright yellow, poppy-like flowers cover the plant in spring. They can be propagated from cuttings taken in summer and are pest and disease free.

Remember when setting plants on a steep slope to arrange them in staggered rows. Make an individual terrace for each plant and create a basin or low spot behind each one (not around the stem) to catch water. Set the crowns of the plants high so they won’t become saturated and rot after watering and make sure mulch does not build up around the stem.

Design trends

Lessons from the Garden

All trees, including redwoods, communicate with each other.

My friend, Evan, often shares interesting studies about plants. Did you know that older trees share intelligence with young trees? Scientists have recorded how birch trees use electrical signals to communicate. How do they do this?

All living organisms have an electrical system. This study showed that the older trees, who had prior knowledge of an event like a solar eclipse, shared this knowledge hours ahead of time with younger trees. Because a tree relies on normal day-night cycles to transport nutrients and regulate water and reproduction, upsetting their internal clock, even briefly, can divert energy from defense chemical production which keeps pathogens and predators at bay. Sharing this information by the elders in the forest protects the young who may not have experienced such an event before.

What other fascinating things do plants do? I was very intrigued reading an article in Audubon magazine by Nathan Ehrlich. Scientists have discovered that plants give off electrical impulses in response to threats. Polygraph expert and former CIA interrogation specialist Cleve Backster confirmed this when, on an impulse, he hooked up a tropical dracaena to a polygraph and threatened the plant with a flame. The dracaena displayed the same electrical signals that people do when they lie. From lettuce to bananas, the results were similar.

Biologists Baldwin and Schultz published work suggesting that some plants can communicate through the air. When the researchers threatened poplars and maples they found that nearby trees, with no physical contact, released defensive chemicals that inhibit digestion, thus hindering predators’ ability to consume the trees leaves or bark.

Plants have many ways to defend themselves. One common way is by being poisonous or irritating. You can get severe eye burn if you get the toxic sap from a euphorbia in them. You just have to accidentally rub some sap near your eyes to trigger a reaction that will require a trip to Urgent Care. The pain can last for days and has been described as a very painful experience. Euphorbias are very deer resistant and drought tolerant and are being used more and more in gardens. Great plant that requires respect.

Many of us are growing milkweed (Asclepias) to attract monarch butterflies. The milky sap from this plant protects the monarch from being eaten and can cause the same painful burning of the eye. I read of a case where a gardener’s clothes brushed some stems while she was tending the garden. Later she wiped the sweat out of her eyes and didn’t realize she had also touched her pants. She ended up with cornea burn causing temporary blindness and had to take strong pain relievers and steroids to elevate the pain. Yikes.

Design trends

Groundcover Ideas for a Changing World

Radiant manzanita grows well in partial shade.

Faced with what to use to keep down weeds when wood chips aren’t allowed? Well, you’re not alone. Although wood chip mulch is good for the health of your soil and your plants, it’s not recommended per new Cal Fire regulations within 30 feet of a structure. Years ago I had a request from a client faced with just this dilemma. Here are some of the ground covers I recommended for her garden and for others in the past.

Living ground covers add beauty to the garden while holding the soil in place and preventing erosion. They contribute to soil health by encouraging microorganisms. A garden wouldn’t thrive as well without groundcovers.

Groundcovers are like a fancy carpet in the garden.They add richness and beauty under trees and become the stars of the show in sunny spots. Groundcovers reduce maintenance by preventing weeds and reduce watering by acting as a living mulch.

When choosing ground covers, 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 consider whether you want a sweep of the same plant or a tapestry effect with a variety of plants. Using more than one type of plant allows you to work with foliage contrast adding pattern to the composition.

Common Snowberry or Creeping Snowberry (Symphoricarpos) will hold the soil on steep banks. This native tolerates poor soil, lower light and general neglect. Evergreen Currant (ribes viburnifolium) and creeping mahonia also tolerate shady conditions. All the low growing ceanothus are great choices for sunnier spots as are the manzanita groundcovers. Smaller natives that put down deep roots are yarrow, coast aster, California fuchsia, wild grape, mimulus, buckwheat, wild rose and salvia including ‘Bees Bliss’.

Low water-use non-native groundcovers like cistus salviifolius, grevillea lanigera, rosemany prostratus, rubus pentalabous, correa and sarcococca are also good low-water choices.

Remember when setting plants on a steep slope to arrange them in staggered rows. Make an individual terrace for each plant and create a basin or low spot behind each one – not around the stem – to catch water. Set the crown of the plant high so it won’t become saturated and rot after watering or rain and make sure mulch does not build up around the stem.

To create stunning combinations of ground cover plants. choose 5 or 6 styles and repeat them in small drifts to carry the eye through the composition. Add grasses for linear texture. Good candidates are Blue Oat grass, a non-spreading clumping grass with silver leaves. Carex elate ‘Bowles Golden’ is a spectacular evergreen ornamental grass and Carex tumulicola (Foothill sedge) is another good choice for a grass-like plant.

There are many more choices for groundcovers that grow in the shade. Stay tuned.
Take the opportunity to survey your garden for bare spaces that can come alive with added texture and color.

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