GARDENING WITH NATURE

Not all plants like the Okanagan

Popular Garden Plants That Struggle Here

Rhododendrons, azaleas, hydrangeas, and most Japanese maples (Acer species) may dominate garden centres but they’re fighting an uphill battle against this valley’s unique environmental conditions.

The most fundamental obstacle these plants face in the Okanagan is soil chemistry.

Rhododendrons, azaleas, and most hydrangeas are acid-loving plants that thrive in soils with a pH between 4.5 and 6.0. Unfortunately, Okanagan soils typically range from neutral to alkaline, often sitting between 7.0 and 8.5 pH. This alkaline environment creates a cascade of problems for acid-preferring plants.

In alkaline soils, essential nutrients become chemically bound and unavailable to plant roots, particularly iron, manganese, and zinc.

The result is chlorosis – that telltale yellowing of leaves while veins remain green – which weakens plants and makes them susceptible to other stresses.

While gardeners can attempt to acidify soil with sulphur or aluminum sulphate, maintaining the necessary pH in naturally alkaline conditions requires constant intervention and expense.

Dry Summers and Low Humidity

The Okanagan’s semi-arid climate presents another insurmountable challenge.

With annual precipitation ranging from just 250-400 mm in many areas, the region experiences genuine water scarcity.

Rhododendrons and azaleas evolved in moist, humid environments where their shallow, fibrous root systems could rely on consistent moisture and lots of organic matter. Their large, thin leaves are designed for environments with high humidity and reliable rainfall—not this valley’s dry summers and low humidity.

Hydrangeas also struggle with the Okanagan’s drought conditions. These plants require consistent soil moisture and suffer significantly when subjected to water stress, which is virtually inevitable during the valley’s hot, dry summers.

Most Japanese maples face similar challenges. These delicate trees prefer consistent moisture and protection from harsh afternoon sun and drying winds – conditions opposite to what the Okanagan typically provides.

Temperature Extremes and Wind Exposure

While the Okanagan enjoys warm summers perfect for viticulture, it also experiences significant temperature fluctuations and harsh winter conditions that stress some of these ornamental plants.

Many rhododendron and azalea varieties that appear hardy on paper struggle with this region’s combination of cold winters followed by rapid spring warm-ups, which can trigger premature budding. That can then be followed by frost damage to those tender new buds.

The valley’s frequent winds compound these problems. Strong, dry winds increase water loss from plant tissues and can physically damage the brittle branches of Japanese maples.

Rhododendrons and azaleas, with their broad evergreen leaves often lose moisture faster than their root systems can replace it.

Why Microclimates Rarely Solve the Problem

Some gardeners attempt to create microclimates to accommodate these plants: installing irrigation systems, adding shade cloth, and amending soil annually.

While occasionally successful in the short term, these solutions often prove unsustainable.

The constant inputs of water, acidifying agents, and organic matter required to maintain suitable conditions are both expensive and environmentally questionable in a water-scarce region. Moreover, even with careful microclimate management, these plants rarely achieve the robust growth and spectacular displays they’re known for in more suitable climates.

The result is often a disappointing performance that doesn’t justify the ongoing investment.

Choosing Plants That Belong Here

Rather than fighting against the Okanagan’s natural conditions, successful valley gardeners embrace plants that thrive in alkaline soils and dry conditions.

Native and adapted plants like penstemon, lavender, yarrow, ornamental grasses, and xeric trees and shrubs provide beauty without the constant struggle.

The Okanagan’s unique climate offers opportunities to grow plants that would struggle elsewhere – Mediterranean herbs, drought-adapted perennials, and heat-loving annuals that coastal gardeners envy.

By choosing plants suited to local conditions, gardeners can create stunning landscapes that celebrate the region’s natural character while conserving precious water resources.

The key to successful Okanagan gardening isn’t forcing unsuitable plants to survive, but discovering the remarkable beauty of plants that naturally call this unique valley home.

A variety of sedums and ornamental grasses instead of coastal perennials

The relationship between plants, pests, and beneficial insects represents a natural system of checks and balances. By supporting these natural predators, we align ourselves with ecological processes refined over millions of years.

Rather than fighting against nature with chemicals and barriers, we can harness these allies to create gardens that not only produce beautiful plants but also support diverse wildlife communities.

The next time you spot a lacewing, soldier beetle, or even a spider in your garden,
consider yourself lucky to be witnessing nature’s pest control experts at work.

GARDENING WITH NATURE

Article by Sigrie Kendrick

Leave Seed Heads for a Winter Garden

In the world of gardening, we often focus on the fleeting glory of flowers with their vibrant colours and sweet fragrances that mark the peak of a plant’s ornamental appeal.

Yet there’s a quieter, more enduring beauty that emerges after the petals fall—one that extends the garden’s visual interest well beyond the traditional growing season.

Magical Seed Heads

The seed heads of xeric plants offer architectural interest, providing structure, texture, and movement that can transform a fading landscape from dormant to dynamic.

Among the most spectacular examples is Pulsatilla, commonly known as pasque flower or prairie crocus.

After its silky, bell-shaped blooms fade in early spring, this hardy perennial produces seed heads that are nothing short of magical. Each seed develops a long, feathery plume that catches light and moves with the slightest breeze, creating an ethereal display that can last for months.

These silvery, gossamer structures rise above the plant’s finely divided foliage like wisps of smoke. In late afternoon light, a patch of Pulsatilla seed heads becomes luminous, transforming an ordinary garden corner into something special.

The ornamental value of these seed heads extends beyond their immediate beauty. They provide crucial interest during the lean dormant months when many gardens lack structure.

While other perennials retreat underground or become mere stubble or sticks, Pulsatilla’s seed heads create focal points that draw the eye. They’re particularly effective when planted in drifts, where their collective movement creates a sense of flow that animates the garden even on still days.

Pulsatilla seedhead left to add interest to the garden

Seed Heads Making a Bold Statement

Achillea millefolium seedheads in a winter garden

The Drama of Allium Seed Heads

Globe allium seedheads in a fall garden

Sigrie Kendrick is a master gardener and executive-director of the non-profit Okanagan Xeriscape Association.

Our Plant Database features more than 500 plants tested and ideally suited for the unique challenges of gardening in the Okanagan’s extreme climate, iincluding the plants in this article.

GARDENING WITH NATURE

Article by Sigrie Kendrick

Creating Vital Food Sources

The Okanagan Valley’s unique climate and ecology make it a crucial habitat for both year-round resident birds and winter visitors.

By thoughtfully selecting and planting native trees and shrubs that provide food during the harsh winter months, homeowners and landowners can create vital food sources for local bird populations while maintaining our region’s natural biodiversity.

Snowberry (Symphoricarpos albus)

Landscaping Tips

Care and Maintenance

While native plants generally require minimal maintenance, some care during the establishment period ensures long-term success. Water deeply but infrequently during the first two growing seasons to encourage deep-root development. Avoid fall fertilization which may promote late-season growth vulnerable to winter damage.

Resist the urge to prune away all berries and fruits in fall cleanup. These food sources become increasingly valuable as winter progresses and natural food becomes scarcer. Similarly, leave some leaf litter under shrubs and trees, as ground-feeding birds often forage for seeds and hibernating insects in this natural mulch.

Beyond providing crucial winter bird food, establishing native plants creates year-round habitat value. These plantings support native pollinators during flowering periods, provide nesting sites in spring, and offer summer shade and shelter. As plants mature, they become increasingly valuable components of the local ecosystem, contributing to the Okanagan Valley’s biodiversity while providing endless opportunities for bird watching and nature appreciation throughout the winter months.

Check our Plant Database for more information on the plants mentioned above.

Sigrie Kendrick is a master gardener and executive-director of the non-profit Okanagan Xeriscape Association.

GARDENING WITH NATURE

Article by Sigrie Kendrick

Glorious Ground covers

Nature abhors a vacuum

It has been said that Nature abhors a vacuum and I have often reflected on this old adage when
planning and planting gardens.

If you have a plant there, chances are, you won’t have a weed. This is especially true when considering ground covers, which act as an organic living mulch and don’t need to be constantly topped up as you would with a composted mulch such as Glengrow or Nature’s Gold. These living mulches mimic what happens naturally on the forest floor and include all the benefits we associate with mulch, in that they act as a weed suppressant, they moderate soil temperature, and they conserve soil moisture.

Whether you have a baking hot, sunny location, a spot with deep shade, or anything in between,  there is a ground cover to meet your needs.

Ground covers by location 

For instance, the Moroccan Pincushion Flower, or Pterocephalus depressus, is a fantastic choice for those hot, sunny areas in your garden. This distinctive ground cover features greyish-green crinkled leaves which are tolerant of light foot traffic such as when used in-between flagstones.

Many low-growing thymes also suit such spaces where there is some foot traffic. Pterocephalus depressus is hardy in zones 4-8 where it will form an evergreen mat a few inches high with a spread of 18 inches. This ground cover flowers in late spring to summer with silvery-pink blooms similar to Scabiosa which then transition into attractive silver seed heads. The blooms of Pterocephalus depressus are a magnet for a large variety of butterflies.

One of my favourite ground covers for a sunny to part-shade location is Persicaria affinis ‘Dimity’. Also known as Himalayan Knotweed or Fleece Flower, this ground cover is as the common name suggests, native to the Himalayas, where it is found at altitudes up to 15,000 feet.

In our hot Okanagan summers, this Persicaria benefits from some afternoon shade where it will put on a display of rose-red blooms, aging to pale pink, from July to October. Ultimately the flowers turn brown and remain on the plant, offering winter interest as well. Persicaria affinis reaches a height of 6-8 inches and a width of two feet. The leaves of this perennial turn brilliant bronzy-red as the temperature falls in the autumn, further adding to its value.

Lamium maculatum, known commonly as Spotted Dead Nettle, is an extremely versatile and easy-to-grow ground cover for a partial or full-shade location. This herbaceous perennial is hardy in growing zones 4–8 so completely appropriate for gardens in the Okanagan, where it will brighten a shady area with its heart-shaped variegated leaves, even when not in bloom.

The cultivar ‘White Nancy’ features silvery green leaves with a thin dark green margin and small white, hooded flowers. Lamium maculatum is extremely long blooming, beginning in late spring and continuing for months with some re-bloom in the fall. This ground cover is virtually disease and pest-free and is not favoured by deer.

It is extremely easy to propagate Lamium maculatum by stem layering. Simply push a stem which is still attached to the mother plant, into the ground and cover it with soil, leaving only the tip visible. This tip will soon form a new plant.

A great candidate for adding colour to the late summer and fall garden is Creeping Hummingbird Trumpet ‘Orange Carpet’ or Zauschneria californica, which hummers love, and which spreads with underground stems. It does well in dry, sandy to rocky, well-drained soils on slopes.

Lastly, there are a wide variety of sedums (commonly called stonecrops) which provide both colourful leaves and flowers, thrive in hot and dry locations, attract pollinators, and have great resistance to heat and drought. In fact, stonecrops can be found growing wild on some of our rocky, dry slopes around the Okanagan Valley, proof of their fantastic toughness.

Try a mass planting of several, including some of these low-growing varieties: Sedum repestre ‘Angelina’, Bertram Anderson Stonecrop, Dragon’s Blood Stonecrop, Fuldaglut Sedum, Mossy Stonecrop, Rose Carpet Stonecrop, Russian Stonecrop or Spreading Stonecrop.

Check our Plant Database for more ground covers as well as more information on those mentioned above.

Sigrie Kendrick is a master gardener and executive-director of the non-profit Okanagan Xeriscape Association.

GARDENING WITH NATURE

Article by Sigrie Kendrick

Great Garden Choices

Clearly, change is afoot when it comes to gardening in the Okanagan.

Many of you may remember a column two years ago, in which I decried some of the garden choices featured on that summer’s public garden tour.

The chosen gardens were stunningly beautiful, of course, but featured plantings which would be unsustainable, when, not if, stringent water restrictions were implemented.

One garden was all hydrangeas, which require considerable water, and another consisted of 10 acres of turf grasses, beautiful in their own way, but by no means sustainable in our hot and dry summers.

I was elated this year to see many gardens on the FlowerPower garden tour focusing on both sustainability and water-wise gardening. Four of the nine gardens featured had no turf in their front yards. That’s right, no grass.

One had an enormous patch of flowering thyme, which was absolutely beautiful. If no one had been watching, I would have laid down in it so that I arose clothed in its delightful aroma.

Another garden featured a stunning meadow planting comprised of native and non-native xeriscape plants. I was in heaven.

Meadow plantings look deceptively easy but they are actually one of the hardest to master and this design team did master the meadow garden.

Yet another garden featured beds of drought-tolerant plants and shrubs accessed via a path planted with xeric groundcovers.

There was a cactus garden. Another featured garden was planted with xeriscape plants that also had to be wildlife-resistant. In fact, mere minutes after the tour ended and we left that property, the owner took a video capturing a young bear swaggering past.

Wow, what a difference a couple of years have made. Rather than leaving the tour disheartened and despondent, I left higher than a kite, grinning from ear to ear. Thank you to all involved for acknowledging today’s reality and showcasing gardens created by gardeners, for gardeners, gardens which are not only aesthetically-pleasing but also environment-conscious.

Typically, volunteers working on the tour are given a pre-tour, enabling them to see all the gardens on the day prior. There was something different this time. The energy was new and fresh. The gardens featured were vastly different from each other but all were stunningly beautiful and thought-provoking.

If these gardens are any indication, then we are actually changing, We, as gardeners, are making choices that are not based on an outdated perception of beauty. Instead, we are seeing beauty in the imperfect, the uncommon, the sustainable, in plant selections chosen less for our eyes and more for the benefit of pollinators and even edibility. What a monumental shift.

Many of the plants featured on the tour can be found on both our plant database and at makewaterwork.ca. This spring, the Make Water Work Plant List was updated to include FireSmart indicators for the plants on the list, thereby allowing you to choose both drought-tolerant and fire-resistant plants.

The Make Water Work challenge encourages homeowners to pledge to make water work smarter on their landscapes. Think about how you use your water and how you can make better choices about that consumption. 

I will be touring Okanagan nurseries and garden centres throughout the gardening season, supporting the many benefits of the Make Water Work plant list and campaign. Keep an eye on our social media for my schedule and stop in to say “hi” and to talk all things xeriscape.

Instead of front lawn, this Kelowna homeowner opted to plant a wild meadow with drought-tolerant gaillardia and blue flax, along with other perennials, for this showy front yard that was part of this year’s Kelowna Garden Tour.

The Okanagan Xeriscape Association is grateful for the ongoing financial support of the Okanagan Basin Water Board and is proud to be collaborating with them on their Make Water Work campaign.

Sigrie Kendrick is a master gardener and executive-director of the non-profit Okanagan Xeriscape Association.

A Pollinator-Friendly Garden

Article by Pat Zander

Pollinator Attraction

My husband and I have always tried to attract birds to our garden. That meant planting shrubs
and perennials that would be sources of food and shelter, and minimizing the use of pesticides
that might harm.

Then we got a hive of honey bees and found that many of the same principles apply. In
particular, bees need a good and consistent source of pollen and nectar-rich flowers during the
warm season. And being very careful with pesticides is even more critical. As they feed, they
are moving pollen around and fertilizing the flowers. The majority of our food crops need these
busy little critters to accomplish this for them before they can produce seeds or fruit.

At one time, I thought there was nothing more entertaining in the garden than watching a
couple of robins bathe in the fountain. However, watching a bee wiggle her way into a tubular
flower and then wiggle back out, covered with pollen, is right up there too. It is a huge bonus
that I am now more aware of all the other pollinators that come our way. With awareness
comes appreciation. I’ve seen three different species of bumblebees “working” the same
patch of flowers, a tiny bee the size of an ant navigating a Hydrangea bloom, and the delicate
scalloping leafcutter bees make on a rose leaf.

Some Familiar Easy to Grow Favourites

Early Spring:
Crocus | Glory of the Snow | Pasque Flowers |  Snowdrops |  Tulips | Hazelnut | Pussywillows

Late Spring:
Allium |  Lilac | Saskatoons | Elderberry | Blossoming Berries |  Blossoming Fruit Trees and Shrubs | Oregon grape

Summer:
Beebalm |  Catmint |  Coneflower |  Dill | Fennel | Globe Thistle | Hyssop |  Jupiter’s Beard | 
Lavender |  Lambs Ears | Mint | Russian Sage | Salvia; | Snapdragons |  Veronica |  Yarrow | Butterfly Bush | Ninebark | Rose of Sharon

Late Summer into Fall:
Autumn Joy Sedum | Sunflowers |  Bluebeard (Caryopteris) | Russian Sage

I have mentioned only the plants in our garden which I know to be pollinator favourites. There
are hundreds more. A quick search on the internet will provide lists of appropriate choices;
borderfreebees.com is a good one. Also, do check out the plant list and images on OXA’s Pollinator Garden in the UnH2O Demonstration Garden on this site. 

It is also worth noting that native plants are the most appropriate for feeding native insect
species. Bonus that they are really easy on the water.

Living in the Okanagan where fruit growing is an important industry, gives us even more reason
to encourage healthy populations of pollinators.

Oh, and if you happen to have a few dandelions in your lawn, you are serving bee candy. Now
there’s an excuse to avoid hours on your knees digging them out.

GARDENING WITH NATURE

Article by Sigrie Kendrick

Think outside the box when prepping for winter

As gardeners, let’s remember to switch up the traditional garden tasks and think in a different direction: perhaps a more environmentally friendly one, that also provides us with more winter garden interest.

For instance, fall is the time of year when ornamental grasses shine. Many are in bloom and at the peak of their beauty.

What poet within us wouldn’t be charmed by the gentle way their graceful seed heads sway in the breeze and dance on the long stalks they’ve been growing all season? Grasses really add movement to your garden—unless you chop them down prematurely.

I recently had the opportunity to consider the importance ornamental grasses hold in our gardens as I cut down literally hundreds of Calamagrostis x acutiflora ‘Karl Foerster’, commonly known as Feather Reed grass, at a client’s property.

So often clients want their grasses razed to the ground before the onset of winter as they
perceive the standing grasses to be “messy” rather than graceful.

Often, land care providers such as landscapers are all too happy to oblige as that means one less task facing them in the spring.

Instead of this perverse desire to tidy in the fall why not take into consideration all the benefits of leaving ornamental grasses over the winter?

What about ecology?

From an ecological standpoint there also are many reasons to leave your ornamental grasses and your perennials standing over the winter. They provide needed habitat for birds and a myriad of other wildlife, as well as for beneficial insects to overwinter.

The seed heads of ornamental grasses and also annuals and perennials which have gone to seed, provide food for birds, who have to forage widely during the colder months, just to survive. They also provide great erosion prevention and slope stability, especially where wildfire has run through the previous season.

The time to shear your ornamental grasses is when you begin to see new growth at the base sometime in spring. Then, don’t toss out the cut grass. Instead, find a spot in your yard where it will be out of your way, but will provide valuable habitat for beneficial insects.

Perennials can also be pruned in early spring, when new growth begins to be visible, while annuals can be pulled out as soon as the ground softens in late winter or early spring.

Remember too that the fallen leaves from deciduous trees should also be left where they fall, rather than being neatly raked up and composted elsewhere in the fall. Those rotting leaves are like gold to a gardener and they provide habitat for insects and wildlife while they decompose over winter.

They also suppress weed growth and protect the roots of perennials over winter and what’s left can be gently dug into the soil come spring.

So, leave the leaves, don’t mow down the grasses and allow perennials and annuals to go to seed (unless they tend to be invasive!)

Article by Mark Godlewski

While it is a complex topic, the main tool used by the horticulture industry to judge which healthy plants likely to survive winter conditions is Plant Hardiness Zones. Most nursery plants are assigned a Plant Hardiness Zone based on their ability to survive winters in a given climate. Those zones range from 1-13 and are based on the harshest historical winter conditions averaged over a period of 20 or 30 years. Zone 1 represents the worst winter conditions.

You can see the Government of Canada plant hardiness zones displayed in map form (see Figure 1). These small-scale maps, however, cannot capture local variation. That is why looking up your municipality is a better option using the following Government of Canada website.

Canadian Government Plant Hardiness for BC

Figure 1 – Canadian Plant Hardiness for BC