Design trends

All About Ceanothus

With deep blue blossoms Celestial Blue Ceanothus blooms for almost 9 months of the year.

When the huge numbers of California Tortoiseshell butterflies showed up around here recently, I learned a lot about the different species of ceanothus and how dependent we are on this plant. Because most of us live near or in a Wildland Urban interface we are aware of the benefits of ceanothus and other native plants. From erosion control to habitat, to seed and nectar for pollinators, birds and butterflies, ceanothus is a most valuable plant. A visit to any local nursery will tempt you to get one of each for your own garden. But are cultivars or “nativars” of ceanothus as valuable as native ceanothus?

Research is ongoing but there are only a few studies comparing the nutritional value of straight native species to cultivars or nativars. Many may have as high en ecological value as native species but this is not absolute. Dark foliage, for instance, does not provided the nutritional value for leaf-eating larvae. There is so much that we need to study.

The groundcover varieties I have used in landscape include Anchor Bay, Carmel Creeper, Heart’s Desire, Centennial and Diamond Heights. If deer frequent your landscape you should stick with Anchor Bay, Heart’s Desire and Centennial but the others are great in protected areas.

One of the upright types growing everywhere in the Santa Cruz Mountain is ceanothus thysiflorus. It’s one of the earliest native shrubs to bloom in our area. It grows along a narrow band close to the coast from Monterey to southern Oregon. There are many nativars of this variety. I like Julia Phelps with those electric blue flowers. It’s a hybrid of Wartleaf Ceanothus and Santa Barbara Ceanothus It’s similar in appliance to another popular nativar called ‘Dark Star’.

A great variety I often use when designing a garden is Ceanothus ‘Concha’ because it will accept summer water more forgivingly than most and tolerates clay soil more than other species. Joyce Coulter ceanothus also tolerates clay, summer irrigation and shearing better than other cultivars. It’s a good bloomer, drought tolerant and is covered in spring with wildly fragrant blue three-inch flower spikes.

Ceanothus is often said to be short lived. Most varieties need good drainage, little summer water and don’t need soil amendments. In their wild conditions ceanothus plants have a natural life cycle of 10-15 years although some live longer.

Several members of the ceanothus family can form a symbiotic relationship with soil micro-organisms and fungi, forming root nodules which fix nitrogen. This is a reason why fertilizing is not normally recommended. Adding fertilizer might kill off the good micro-organisms. Ceanothus are better left fending for themselves.

Ceanothus provide excellent habitat for birds and insects. They are good for attracting bee and pollinators and are the larval host plants for the beautiful ceanothus silkmoth. Ceanothus seed is readily eaten by many local birds. Planting a ceanothus is an important step to attracting more birds and wildlife to your garden.

Early California Indians used the fresh or dried flowers of some varieties for washing, lathered into a soap. it has been said to relieve poison oak, eczema and rash.

Design trends

Butterflies Galore

American Painted Lady butterflies taste with their feet

Recently we were visited by hundreds of butterflies. One made it into the house as they fluttered around me when I opened the screen door. He’s going out today to join the other California Tortoiseshell (Nymphalis californica). You would think with so many of these beautiful subjects to photograph, I could have gotten the perfect shot but alas, nary a one landed on any of my nectar-rich flowers, not even the buddleia. They were looking for ceanothus and were soon trending on local social media. Where did they come from and why so many this spring?

The California Tortoiseshell butterfly is a common butterfly that lays its eggs on ceanothus. After the CZU fire we have an abundance of this succession plant as the soil-stored seeds germinated after the fire broke their dormancy. These seedlings can account for more than half of the plants present in burn areas. If you’ve visited Big Basin State Park or any of the other burn areas, ceanothus are pretty darn happy with all the extra space and sun they are now getting.

Tortoiseshell butterflies have an interesting life cycle as do all butterflies. With three generations per year, they fly here from the Sierra foothills where they lay their eggs on ceanothus. Then those hatch and feed, morph into butterflies who fly to the foothills to repeat the process. Larval food plants include several species of Ceanothus. Adults feed on flower nectar, sap, fruit and mud. They live for 10 months or more.

The Tortoiseshell is no stranger to our mountain. After the Lockheed fire this same phenomena happened when the ceanothus were head-high. After hatching here they took flight to the mid-elevation Sierra Nevada to lay eggs on a different species of Ceanothus. After that generation denuded the patches of Ceanothus there those adults flew to the highest elevations to eat yet a different species of Ceanothus. Then the adults flew all the way back to Monterey Bay to lay eggs on our Ceanothus and start the cycle over again.

We have about 90 species of butterflies in the Monterey Bay area. Many of these occur only in our mountains, forests and chaparral environments. They are easy to attract and make a permanent feature in your landscape. Here’s how.

A butterfly garden should include plants that accommodate all stages of the life cycle – egg, larvae, pupa and adult . When both adult nectar and larval host plants are available, they will attract and support a butterfly population. In addition to the right plants, your garden should also have sun, a water source, protection from wind and plants in clusters. When maintaining your garden avoid the use of insecticides, including BT.

As adults, most butterflies feed on the nectar of flowers. Some local butterflies, like the Mourning Cloak and Red Admiral, feed primarily on rotting fruit or tree sap for moisture and nutrients while the California Sister feeds on aphid honeydew.

In the larval stage, most butterfly species are limited to a single plant family and occasionally a single genus. To attract more Western Tiger Swallowtails, for instance, provide larval host plants such as willow, sycamore, alder, big leaf maple, sycamore, plum and ash. Common Buckeye lay their eggs on mimulus and verbena while California Sister use the coast and canyon live oak. Planting a variety of grasses and shrubs like ceanothus, buckwheat, coffeeberry, bush lupine,manzanita and perennials like redwood violet, California aster and wallflower will attract a variety of local butterflies. If your garden is near a wild area that naturally supports the caterpillar stage, you can plant just the nectar plants to attract butterflies to your garden.

Filling your garden with nectar producing flowers is the fun part. Adult butterflies rely on sugar-rich nectar for their daily fuel. Different species have different flower color and shape preferences. Many butterflies produce scents that attract the opposite sex and many of these scents smell like the flowers that they are attracted to and visit. The scent of these butterfly-pollinated flowers may have evolved as an adaptation to ensure their survival.

Butterflies typically favor flat, clustered flowers that provide a landing pad although larger butterflies can feed on penstemon and salvias while hovering. Unlike bees, butterflies can see red and are attracted to brightly colored flowers. Pink, red, orange, yellow and purple are the most attractive nectar source flower colors but they also use blue and white.

Consider the blooming time of each plant. Having plants blooming in the sun for many hours in the day will lengthen your viewing time. Nectar rich flowers include yarrow, aster, verbena, scabiosa, buckwheat, toyon, salvia, erysimum, zinnia, lantana and coneflower.

In addition to nectar, butterflies need a source of water and salts. A patch of mud kept wet year round or a shallow depression lined with pebbles and kept moist will work fine. Also provide some flat rocks for them to bask in the sun in an area protected from the wind by shrubs.

Having a garden filled with birds, bees, butterflies and other pollinators is fun and easy.

Design trends

Why Plant California Natives?

Formerly known as zauchneria, California Fuchsia ( epilobium canum) is a hummingbird magnet

Most of us would love to have a garden containing all California native plants growing happily in an ecosystem where everybody wins- birds, bees, insects, wildlife and us, of course. Our garden would contain flowers, shrubs, grasses, ground covers and trees all providing food, water, cover and nesting places. Trouble is most people are managing existing landscapes and gardens with a variety of established trees and plants, often including vegetable and herb gardens. So what’s a good citizen and steward of the planet to do?

National Wildlife Federation recommends that yards strive for 50-70% native plants. This refers to the biomass of the plants in the garden and not the number of plants so this is easier than you think to help the pollinators, contribute to soil health and control erosion.

California is a vast domain when it comes to natural features and different soils. From hills and mountains to deserts, valleys and ocean bluffs, there are 6000 plus plant species within our borders. Hundreds of these are showy and useful plants worthy of cultivation in our garden. Some, like ceanothus, have already been cultivated for a century or more, both here and abroad.

There are features of the California landscape that present a certain flavor and seasonal progression, quite distinct from that of the subtropics and year-round, moist forests that many traditional garden plants come from. Plants of hilly and mountainous areas are often found in rocky or sandy soils and require well-drained garden soils. Many plants of the chaparral have poor resistance to the root pathogens that thrive in a warm, moist soil and may not tolerate typical garden style irrigation in summer.

Matching or creating the right conditions is the key to success to grow California natives. Planting on a raised mound or berm, for instance, is one way to drain water away from sensitive crowns. Knowing where in California a given native plant comes from can help you make the right decisions.

That being said there are many natives with an amazing broad tolerance of different conditions. Toyon (Heteromeles arbutifolia) grows in both sandy and clay soils as does yarrow (Achillea millifolium) which is also a good cut flower. Carex grass and Seaside daisy (Erigeron glaucus) also do well in most soils.

If you garden in clay soils, good native shrubs are Western redbud, manzanita, spicebush, bush anemone, ceanothus, garrya, Pacific wax myrtle, Western mock orange, blue elderberry, mahonia, California wild rose and snowberry. Native perennials for clay soil include coral bells, sticky monkeyflower (a good cut flower), salvias, deer grass, rubus and Dutchman’s pipe vine.

Sandy conditions require California natives that are decidedly drought tolerant. You may already grow many of our manzanitas and ceanothus. But do you also have lupine, lavatera, coffeeberry, buckwheat, fuchsia-flowering gooseberry, purple sage, wallflower or the beautiful Douglas iris?

Then there are the folks that live in the shade. Native plants from canyons and riparian areas will do well in your garden. They require some summer watering but that’s all. Native shrubs that tolerate bright shade are manzanita, spicebush, bush anemone, ceanothus, mahonia, Pacific wax myrtle, any of the ribes, wild rose, snowberry and huckleberry. Perennials for color are columbine, Western bleeding heart, California. fuchsia, Douglas iris and coral bells.

Where ever you garden, to provide food, nectar or berries for our winged friends be sure you have some flowering currant, sticky monkey flower, coffeeberry, salvia clevelandii, Dutchman’s pipe vine, wax myrtle, California fuchsia and aster chilensis.

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