All posts by Jan Nelson

I am a landscape designer and consultant in the Santa Cruz mountains in California. I write a weekly gardening column for the Press Banner newspaper. I am also a Calif. Advanced Certified Nursery Professional and managed The Plantworks Nursery in Ben Lomond, Ca. for 20 years.
Design trends

Best Native Plants for Containers

Penstemon heterophyllus ‘Margarita B.O.P.’

A couple weeks ago I wrote about including California native plants in your garden. Since I have limited ground to garden I mostly have containers and have been quite successful as long as I match the sun or shade to the right plant. You’ve heard it before: “Right Plant, Right Place”
So here are some tips on native plants that do well in containers.

At my front entry that gets morning sun only I have a huge coral bells (Heuchera micrantha) that started out as a cutting wrapped in wet paper towels that a neighbor had found growing at the edge of the forest nearby. It loves it here. Other plants like salvia would not be happy there at all.So it’s definitely the right plant for the right place.I ’ll have to divide and transplant it next spring but it blooms for such a long time and the hummers love it so I never want to disturb it.

Adding California natives to my collection of container plants has been a goal for a long time. Besides attracting birds and wildlife to the garden they use less water than most container plants plus they are beautiful.

Gardening in containers is easy. You can control the soil, water and light and the gophers can’t undermine your efforts. There are a lot of California native plants that do well in containers and I’m going to place them where both the birds and I can enjoy them.

For some of my largest containers I’ll choose from natives like Western Azalea (Rhododendron occidentale), Deer Grass, Chaparral Pea or Giant Chain Fern. Any of the taller growing ceanothus and manzanita would look great too by themselves or combined with smaller growing plants.

Lewisia

For small to medium containers I can use Conejo Buckwheat, Hummingbird Mint, Penstemon heterophyllus, Mimulus, Woolly Blue Curls or Coastal Daisy, These combine well with colorful Lewisia, Dog Violets or Wild Strawberry.

I might combine a madrone with a Canyon Gray Coastal Sagebrush (Artemisia californica) which grows about a foot high and will trail over the side of the container adding beautiful gray color to contrast with the rich green of the other leaves. I also like the combination of California Hazelnut, Deer Fern, Redwood Sorrel and Wild Ginger.

Some of the most dramatic containers utilize the concept of combining a thriller, some fillers and spiller or two. Not all my containers will use this formula but I seem to be drawn to those that do. Plants in nature can be quite random in the way they grow together and still be lovely. Containers need a bit more order to dazzle and direct the eye.

Thrillers act as the centerpiece of a container. They are usually big, bold and beautiful. Giant Elk Clover is one such California native that is an attention getter. Chilopsis linearis (Desert Willow) is another great subject for containers as it is slow growing and beautiful in leaf and flower. Other architectural natives that will catch your eye as the centerpiece of a container are Hardy Hibiscus (Rose Mallow) and Pacific Dogwood. The thriller goes in the center of the pot or if your container will be viewed from only one side it goes in the back.

Next come the fillers. They can be foliage or flowering plants but they should complement and not overwhelm your largest plant. Usually they have a mounding shape and I’ll plant several around the thriller. Good fillers include Heuchera micrantha and Western Maidenhair fern.

The last plants I’ll add are the spillers which are small and will soften the edge of the container. Redwood Sorrel, Wild Ginger and Miner’s Lettuce are good choices. California Fuchsia would look spectacular with its red or orange flowers and grey foliage spilling down the side of my container.

The best overall soil mix for natives in containers is sharp sand and horticultural pumice added to a good potting soil. Never use perlite or that puffed up pumice because it will float and look terrible. Happy Container Gardening.

Design trends

Beautiful Rhododendrons

Every garden I visit these days has at least one gorgeous rhododendron in full bloom. They can’t help but be spectacular covered with those huge flower trusses. They sure make you stop and take notice. I still miss the two old ones I had in Bonny Doon before the fire. I would time my pruning and fertilizing to get the maximum blooms. They are easy to grow if you remember a few tips.

Because rhododendrons like air in the root zone, amend your soil liberally with organic matter. 50-60% is not too much. If you garden in clay, just plant them in raised beds or berms 1-2 ft above the original soil level. Rhododendrons like moist soil so top dress around your plants with several inches of mulch over the root zone, making sure the stem is not get buried. Pine needles, oak leaves or wood chips are good choices. Never cultivate around the plants as this would injure the surface roots. Finally, most rhodies thrive in partial shade or morning sun. The hot afternoon sun that we get during the summer would burn even those varieties that tolerate some sun. Since their leaves remain on the plant for several years you’d have to live with burnt leaf centers and edges for a long time if they get too much sun.

Rhododendrons contain toxic resins that are more concentrated in the foliage,so weevils have developed a resistance to pesticides along with a tolerance for the toxins in the leaves. Organic or even chemical sprays have little effect anymore according to a study funded by the Rhododendron Society of America and end up killing hundreds more predatory beetles and other beneficial insects in the process.

Applying parasitic nematodes to your soil is one way to control weevils. Other tactics include placing a shallow pan of water under the plant or a soup can filled with soapy water buried up to the top to attract and drown the adults . You can also try banding the trunks with tape or waterproof paper and smearing the bands with a sticky barrier like Tanglefoot. Spreading some coffee grounds under the plants also helps to discourage them from crawling up the trunk after they spend the night at the base of the plant. And if you’re really determined you can hand pick them after dark- effective but not much fun.

There are thousands of rhododendron varieties. By planting early, mid-season and late blooming types you can enjoy those huge, gorgeous flowers for months.

Cheer is one of the showy early bloomers. Large, pink flower trusses cover the 5×5 ft plant. It can take some sun and would be a good candidate if you have one of those gardens that receives and hour or so of afternoon sun.

For April blooms consider Edith Bosley. Similar to Purple Splendor it grows upright to 6 ft.tall but only 4 ft wide. Perfect for narrow spaces. Other mid-season bloomers that would make a splash in the garden include Golden Gate, a 3 ft compact orange hybrid and easy-to-grow, red-flowering Jean Marie de Montegue.

To extend your season add some late season varieties like Lee’s Dark Purple. Growing with a spreading habit to 4 x 5 ft wide, you’ll love its blue-purple trusses. Anah Kruschke also blooms late in spring with lavender pink flowers on a dense 5 x 5 ft shrub. A tough undemanding larger variety is English Roseum. This one grows 6 ft tall with lavender pink flower trusses and blooms in May.

Rhododendrons really contribute to the woodland or shade garden. They are long-lived and deer resistant. I’ve only heard two gardeners tell me that deer ate some of their flower buds last fall for the moisture content. Most likely those deer couldn’t read well enough to read the deer resistant list!

Design trends

Why Native Plants?

California native Siskiyou lewisia grow in rocky, dry soil.

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.

Philadelphus lewisii

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.