Gardeners will give you several reasons for growing native plants in captivity.
Sometimes they are put forth as alibis by those interested simply in natives for native’s sake.
Perhaps more of this group of gardeners are merely following an inner urge for the “wild” or the “simple” rather than the tamed or improved.
But for the person who travels or even for the one who gets about only a little in his state, one reason is valid: the pleasure of recognition.
Growing Natives For The Garden
Suppose one has grown Arctostaphylos (uva-ursi) in a California garden. In that case, one can talk intimately to a friend in Seattle about the plant Northwesterners call kinnickinic.
One can also feel fleeting pleasure at finding on Canadian Rocky Mountain paths a large quantity of ground covers well known among the many unfamiliar kinds there, or revisit with bearberry in the mountains of Maine.
Even a field of lupine seen from an airplane looks more like lupine if one has grown the plant.
Automobiles go too fast, and too few companions want to stop for much enjoyment of plants that grow by the highways, but if one has collected buckwheats, one can guess the genus of an unknown species even at 60 miles per hour.
For a better view of Sierran wildflowers, I recommend Overland Limited.
In these speed days, the Southern Pacific must still go very slowly up the steep grade where the track was laid long enough ago so that now the native plants have almost covered the cuts.
Still, one cannot stop the train, and those not grown at home or often seen before must go unrecognized.
Suppose the pleasure of recognizing plants in the wilds is the best and underlying reason for growing natives.
In that case, there is certainly another: the habits of growth and the natural spread and quality of permanence make certain Western natives excellent for the garden.
Among these natives are several that are especially good for slope planting.
Selecting attractive material for the treatment of banks is the concern of many gardeners, particularly those who want to acquire a ground cover that will thrive with a minimum of maintenance.
Rules For Succeeding With Natives
What are the rules for succeeding with natives?
Here are 6 good tips to remember:
- Buy young, healthy plants.
- Plant in the fall to supply natural moisture in the rainy months.
- Set plants high (not in a basin) and provide good drainage.
- Water the plants often enough to keep the ground moist through the critical summer and fall of the first year.
- Help the plants and routine pruning, feeding, and spraying as needed.
- Avoid spading too close to the roots; it’s better to mulch until the planting covers the slope.
Different Categories Of Natives For Slope Planting
Let’s discuss natives for slope planting in categories of the following:
- Small growers
- Medium growers
- Large growers
Then, they fit into four divisions of tolerance:
- Moisture and shade
- Moisture and sun
- Drought and shade
- Drought and sun
I have chosen to classify these plants according to tolerance because so many will grow suitably in more than one kind of exposure and under one condition.
I will suggest one or two for each category. Obviously, the favorites of those I have grown.
Small Growers
Vancouveria Hexandra Or Vancouveria Parviflora
Vancouveria hexandra or Vancouveria parviflora is a carpeting evergreen trailer from the redwood forests.
The leaf is about 1″ inch across, heart-shaped, deep green when mature, apple green when young, very shiny, of a leathery texture, and closely set on wiry stems which hug the ground.
The flower spray is composed of tiny white or lilac flowers and often grows to 2′ feet in spring.
They are of unusual form, hence the name “inside-out flower.”
As the plant’s width seldom exceeds 10″ inches when grown in the garden, this plant is suitable for a small area. Its availability is limited.
Asarum Hartwegi and Asarum caudatum (Wild Ginger)
Asarum hartwegi and Asarum caudatum are herbaceous spreaders from California and Oregon’s damp, dark woods.
Ginger will thrive only in the soil in which leaf mold predominates. The leaf is 4″ inches across, heart-shaped, rubbery, and has interesting veined markings, sometimes mottled.
The hairy leaf stalks are strong and upright, growing to 6″ inches.
The purplish-brown flower is unusual, but it’s not noticeable because it is short-stemmed and almost hidden by leaves.
In an old California garden, ginger has been used as the finish of an azalea-planted slope above a rock wall 100′ feet or longer.
The Western wild ginger is more handsome than the wild ginger of the East.
It is available in small quantities at specialist nurseries.
Medium Growers
Gaultheria Shallon (Salal)
Gaultheria Shallon is an evergreen subshrub with creeping rootstocks. Salal is a prominent part of the undergrowth of the Pacific Northwest, varying considerably in size (from 1′ to 3′ feet) and texture according to its situation.
For instance, dry California’s low, tough ground cover spreads slowly in competition with other plants and little resembles the long branches covered with good-sized, bright green foliage that florists sell as “lemon leaves.”
The species name, Shallon, is of Indian derivation.
Salal was first collected by the Lewis and Clark expedition after Lewis was revived by an Indian sauce prepared from the black aromatic berries.
The leaves are oval, pointed at the tip, finely toothed, very leathery, dark olive green, and rather glossy.
The stems are stiffly bending, and those which bear the flowers are often bright red with reddish bracts.
In spring and summer, pink and white waxy flowers hang gracefully from the colorful stems.
Salal is a sturdy plant, gradually spreading and appearing richer when given shade and water. It is available at many nurseries.
A smaller, more contained creeper, Gaultheria ovatifolia, is called Western wintergreen.
Tall Growers
Vaccinium Ovatum (California Blueberry)
Vaccinium ovatum or California blueberry is an upright shrub, taller than salal, usually growing 4′ to 8′ feet.
It’s a native of the hills near the Pacific coast, especially the redwood region.
The flowers are similar to salal, but they grow in short clusters from the leaf stems.
The glossy, leathery, neatly arranged evergreen foliage is often used in decoration.
Since this shrub is not widespread or fast-growing, it should be planted in groups on a shady bank, 2′ to 3′ feet apart.
The purple berries are said to make excellent preserves and are available at many nurseries.
Ribes Viburnifolium
Ribes viburnifolium is a spreading evergreen shrub from the West’s shaded foothills, a currant that looks little like a currant.
The leaves are neither crinkly nor ruffled but smooth and leathery. They are oval and about 2’ inches long.
The stems, which are stiff, straight, and branching, have the same reddish tone as the clusters of tiny, rose-colored flowers produced many months of the year.
The evergreen currant grows wide rather than tall, and its spread may be increased by removing the vertical branches and leaving the horizontal ones.
In time, the plant will spread to 6’ feet, while other plants may be obtained from the lowest layered stems.
In the shade, the leaves will be softer and greener. There will be more flowers with some sun, and with water, the plant will grow faster and more luxuriantly.
On a bank, the habit will be more trailing. On a slope planted with trees and shrubs, evergreen currant makes a fine solid ground cover.
The specialist nurseries carry this currant.
Cornus stolonifera is a still larger subject for a bank with moisture.
In early spring, along the banks of streams in the Sierras, you can see the bare red stems of this plant.
Moisture And Sun Preferred Natives
Small Growers
Penstemon Heterophyllus (Blue Bedder)
Penstemon heterophyllus or Blue bedder is a selected form of a Western species, obtainable from the nurseries in flats.
One should obtain healthy stock as penstemon will only flourish if it begins as a fine specimen. Save seed from the best specimens and sow it in flats to increase your planting.
Blue bedder should be grown in large masses so the blue flowers will appear as a sheet of color.
The plants will bloom for many months in spring and summer. However, if the finished stems are cut off, the bloom period will be extended.
The foliage is insignificant, and the habit is somewhat trailing.
Many kinds of beard-tongue, blue, purple, yellow, and scarlet-flowering, are native to the West.
They are conspicuous in the Grand Canyon, Yosemite, and throughout the Sierras.
One form, with magenta flowers, is stunning when seen against the granite ledges of the mountainside.
Mimulus In Variety
Plant breeders have produced varieties from the rather coarse monkeyflower with nice green foliage and lovely-colored flowers, including yellow, cream, buff, apricot, and red.
When familiar with the characteristics of the genus, it is easy to recognize the many wild species of the mountain, desert, and field.
One should select a form with stems more slanting than upright for slope planting.
Medium Growers
Eriogonum In Variety
The buckwheats are beautiful when grown in large groupings of many kinds.
A collection of all the grey ones is especially pleasing. Though they will stand extreme drought, buckwheat will stand regular garden watering and grow more lush, full, and heavy-flowering.
Eriogonum aborescens grows to about 3’ feet and is thickly branched, wide, rounded, and shrubby.
The grey leaves are finely cut, and the stems are brittle. The flower stems are just long enough to project above the foliage.
The heads of tiny, dryish flowers are first apple green, then pink, then rose, then deep rich brown.
If the plant gets too woody after 15 years or so, replace it with seedlings you have collected from around the old plant.
Eriogonum Giganteum (St. Catherine)
Eriogonum giganteum, or St. Catherine’s lace, is a handsome species coming from the islands of Southern California.
- The flower clusters on long, stiff, curving stems are excellent for decoration.
- Pick the flowers in the desired tone and hang them upside down to dry.
- Use them for decorating until they gather too much dust to be attractive.
- The grey leaves are 2′ inches long, and the stems are brittle and woody.
- The shrub is less upright when planted on a bank. Its availability is increasing.
Tall Growers
Physocarpus Malvaceus (Ninebark)
Physocarpus malvaceus or Ninebark grows in rich soil on western mountainsides of the Northwest, Utah, and Arizona.
It grows to 6’ feet in the wilds, and when grown on a bank in the garden, it may be pruned to encourage horizontal growth. The plant layers easily.
This shrub is most handsome in the spring when the new leaves are fresh and bright, light green.
The foliage grows close to the thick, stiff, woody stems. Hawthornlike, 3-inch clusters of cream white, sweet-smelling flowers grow from the leaf axils.
The long stamens make the flowers feathery. As the flowers age, they turn a dusty deep roses. Only a few nurserymen carry Ninebark.
Rhus ovata is another good Western native for bank planting.
Drought And Shade Preferred Natives
Small Growers
Arctostaphylos (Red Bearberry)
Arctostaphylos or Red bearberry. This manzanita is a woody, evergreen trailer that can be found in any of the mountains of North America, in the hilly open woods of the Northwest, or on dunes along the northern part of the West Coast.
It is rated “small” because it is low-growing, even though older plants like the 15-year-old one I grew in my garden may have stems 6′ feet long.
The inclusion of red bearberry in this drought and shade category is more or less arbitrary as I have seen it growing under all conditions.
However, if the plant is situated on a bank in the full sun, it will look better if given water twice a month.
The small oval, glossy leaves arranged on reddish branching stems are dark green in shade and light green when new.
Some turn russet and red when the weather turns colder in the fall.
This trailer blooms profusely in the spring and summer but intermittently throughout the year so that often there will be blossoms together with the green, pinkish to red berries.
The flower is shaped like a closed bell and varies from white to deep pink.
Bearberry will make a full and flourishing bank cover of great permanence, but you must wait for 4 years for the cover to become established and close ranks.
Bearberry should be planted in the ordinary clay commonly found in the West, away from the coast. Nothing needs to be added to the soil before planting.
Bearberry looks better in old age if it is given yearly spraying for thrips or scale and an occasional trimming to remove poor branches. There are wide variations within the species.
The Saratoga Horticulture Foundation has propagated for the market two forms which are superior:
- One with larger, better leaves
- One with bigger, redder berries
The Indians who used the berries medicinally and in the curing of skins gave this manzanita its other common name, kinnikinic.
As it will grow from sea level to 10,000′ feet, the trade has difficulty keeping up with the demand.
Medium Growers
Ceanothus Gloriosus
Ceanothus gloriosus is a native of Western coastal hillsides. Others of the trailing mountain lilacs are drought and shade tolerant, but this one is chosen for its cascading habit when situated on a steep slope.
One plant can cover a space 10’ feet wide by 15’ feet long. The leaf is toothed and shiny, and the lavender flowers are formed in numerous tight, rounded clusters in early spring. Its availability is limited.
Tall Growers
Ceanothus Griseus Horizontalis
Ceanothus griseus horizontalis is a large shrub varying considerably in the species. Some form more upright than others, but all branches at angles are not erect.
Its spread exceeds 12’ feet. It reacts very well to pruning.
In California, its bloom is scattered throughout the year and in the spring. The flowers are a deeper bluish lavender when the plant is grown in part shade.
The leaves are shiny, oval, somewhat toothed, and crinkled.
As ceanothus is long-lived and adaptable to garden conditions, it may be planted in a mixed shrub border and by itself. It is available at many nurseries.
Drought And Sun Preferred Natives
Small Growers
Zauschneria Californica (Hummingbird Trumpet or California Fuchsia)
Zattschneria californica (Hummingbird trumpet or California fuchsia) is a grey herbaceous spreader, native to the dry hillsides of the West, which multiplies by underground stems.
The stems may be cut to the ground in the winter, and new shoots will make a lovely, silvery cover about a foot high in the spring.
In the fall, the grey is studded by rosy-orange flowers. Another trailer with grey foliage is Zauschneria latifolia.
It grows in Western mountains at altitudes of 4000’ to 9300’ feet. It may be difficult to find at the nursery.
Medium Growers
Eriogonums
Eriogonums have many species, some with green foliage, some with grey. Others are trailing, climbing, or shrubby. There are many possibilities in this group.
Arctostaphylos franciscana
Arctostaphylos franciscana is a lovely shrubby manzanita that was first found on the hillsides around San Francisco Bay.
The foliage is leathery and greyish-green, and the procumbent stems are shiny, smooth, and mahogany-colored.
The flower is waxy, almost white, and the berry is about ¼ of an inch across, smooth and fleshy.
The word “manzanita” is from the Spanish word meaning “little apple.” Indians, bears, and chipmunks eat the fruits of the manzanita, and the pleasant acidity makes them good for jelly if one can get enough of them.
Large Growers
Dendromecon Rigida Variety Hartfordi
Dendromecon rigida variety Hartfordi is a bush-poppy that grows on dry, sunny hillsides in middle altitudes.
It may be seen on rough, steep cuts along the highways and is at its best near Santa Barbara, California.
It grows 2’ to 8’ feet high. The leaves are bluish-green, stiff and leathery, narrowly oval, and pointed at the tip.
During all seasons of the year, clear golden yellow poppy-like blooms are produced all over the bush. Quite many horticulturists carry the dendromecon.
Ceanothus
So many kinds are suitable for planting on banks that receive little water that one can hardly go wrong whether choosing a species or one of the several excellent modern hybrids now sold in the trade.