Cultivate a Bat-Friendly garden

Guest Article by BC Community Bat Programs

How can you support the bats?

Spring is at our doorstep! This is the most exciting season for gardeners and nature lovers. This year, we encourage everyone to try something new– gardening for BATS!

The Okanagan is home to at least 14 different species of insect-eating bats – the highest diversity of bats in the province. Supporting pollinators in your garden helps to support bats as they prey on insects at night. Since bats are active from dusk to dawn, having night-blooming flowers in your garden attracts nighttime moths which are a great source of protein for bats. This practice is called moonlight gardening!

Join us in cultivating bat-friendly gardens and nurturing the rich biodiversity of the North Okanagan:

• Start planning early. Opt for native perennial plants – contact local plant nurseries to get your seeds.
• Choose plants with long flowering season or those that flower at different times of the year.
• Variety is key! Pick plants with different flower colour, shape, and fragrance.
• Don’t spring into garden clean up too soon. Wait until temperatures stay consistently above 10°C to start to start raking and pruning. Many pollinators like bees and butterflies are wintering in dead leaves and hollow stems of last-year plants. Bats and snakes sometimes also sleep under leaves and in wood piles.
• Invasive species like burdock can entangle bats and birds. Regularly remove weeds from your garden. If you plan on harvesting burdock, please be responsible and prune out the flowers before they go to seed and become traps for bats.

Invasive species like burdock can entangle bats

If you plan on harvesting burdock, please be responsible and prune out the flowers before they go to seed and become traps for bats.
Photo by: Ken Dzinbal

• Pesticides and chemical fertilizers kill insects and poison wildlife. Practice organic gardening by avoiding chemical products. Try composting to provide organic nutrients in your garden.
• Fact: Bats fertilize gardens with their nitrogen-rich guano (bat poop). Attract bats to have a natural source of guano fertilizer in your garden.
• Switch outdoor light bulbs to “warm” toned or filtered LEDs (under 3,000K) to reduce light pollution that harms bats and other animals. Dimmers, motion sensors, and timers can help to reduce illumination and save energy.
• Keep pets indoors or supervised outdoors to avoid predation on bats and birds.
• Keep dead-standing trees (if it is safe to do so) and mature trees on your property to provide roosting areas for hard-working bats. Peeling tree bark and bark crevices are great homes for bats.
• If you have a lake, creek or wetland by your house – great! Protect natural water-side vegetation; it provides vital food, shelter and water to wildlife.
• Consider adding a garden pond to create a biodiversity oasis in your backyard. Ponds need to be at least 3m wide to serve as drinking sources for bats.

Download the Bat-Friendly Gardening in the Okanagan PDF 

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 (it can be a bit slow to load but there should be a newer version published later in 2024).

Canadian Government Plant Hardiness for BC

Figure 1 – Canadian Plant Hardiness for BC

GARDENING WITH NATURE

Extreme weather taking its toll on gardens

For instance, do not prune your plants in the heat.
Periods of intense heat are stressful for your plants, and pruning, especially thinning, will only serve to
increase this stress.

Removing leaf matter increases the effects of heat on the remaining vegetation, decreasing the humidity
and therefore forcing the remaining leaves to transpire more to cool the plant.

This often has disastrous results.

Another no-no in periods of extreme heat is fertilizing your plants.

Try to make sure your garden has the nutrients necessary for plant health prior to any spike in
temperature.

Adding fertilizer is almost akin to adding salt to your soil as fertilizer essentially makes it harder for your
plants to access the water in the soil. High concentrations of nutrients actually reverse osmosis, the process by which a plant is able to absorb water from the soil. The osmotic pressure is reversed so that the pressure outside the roots becomes greater than inside, making plants unable to access moisture from the soil and they actually lose water back into the surrounding ground.

Planting in the heat of summer is not ideal

Out of necessity, the landscape industry must continue to plant throughout the hottest summer weather but this is far from an ideal situation.

If at all possible delay your planting to the coolness of shorter days in late summer when the ambient air
temperature has decreased but the warm soil necessary for strong root establishment exists.

If you must plant in high heat, at least offer supplemental shade for new plantings by using shade cloth or, in a pinch, an old white sheet.

This shade is even more vital if you are planting in an area of ‘high albedo’. High albedo environments occur where there is a great deal of reflection such as found in a rock garden. This reflective sunlight will damage young plants that can not transpire enough in the high heat to cool their leaves and almost immediately begin exhibiting heat stress.

Unusual snowfall in early November 2022 landed on trees whos leaves had not had time to drop yet

At the other end of the spectrum, severe winter weather caused considerable havoc in Okanagan gardens, as well as in commercial orchards and vineyards.

The weather we have experienced over the last two years has had severe repercussions for our trees, shrubs, perennials, vines, and ornamental grasses.

In the Okanagan Xeriscape Association’s demonstration garden, we saw the complete loss of several Lavenders and Penstemon and extensive injury to several of our trees from the 2022/2023 winter. The Parrotia persica, the Robinia pseudoacacia ‘Twisty Baby’ and the Koelreuteria all have suffered winter damage, and the latter has had to be removed. It’s a heart-breaking loss.

I have heard other Master Gardeners around the valley sharing similar stories of witnessing first-hand deaths of these plants as well as Buddleia, Hybiscus syriacus and various ornamental grasses.

I know that the long warm fall followed by the extreme and abrupt cold experienced in the beginning of November was to blame for much of the damage, similar to your forgotten frozen water bottle exploding, but I wanted to know more. It was hard to ignore that many of our trees held their browned leaves through the winter, never having the chance to drop them as they normally would, with last fall’s sudden lurch from summer into winter.

I consulted with plant pathologist Robert Hogue of Pegasus Horticultural to gain a better understanding of the physiological process which had wreaked such havoc.

Robert explained that it all actually began with the Heat Dome of 2021 when plant tissue was damaged by the extreme heat, registering into the mid-40s.

Like people, plants go into a low-energy state in extreme heat. In survival mode plants do not process as much carbon dioxide, leading to less carbohydrates moving into the roots. This lack of carbon dioxide means the roots receive less sugars which compromises the ability of the roots to absorb the necessary water and nutrients from the soil.

This in turn leads to root death and with the death of large woody roots comes the death of the organism as a whole. This root death also occurred last fall with the abrupt arrival of winter when the roots were still actively growing.

As Robert explained, ‘The abrupt cessation of metabolic activity in the above-ground plant parts meant there was not enough nutrient flow to the roots to complete the suberization process’.

Suberization is the process by which the root walls harden off into corky tissue similar to a callus over a wound. These weakened feeder roots act as an entry for many root pathogens such as Fusarium, Pythium, and Verticillium.

The damage can be immediate, as seen this spring when the plant abruptly died after a seemingly normal leaf-out; but in other cases there will be a slow but inevitable death.

Robert has done extensive research on the hardiness of plant life in the valley and has come to the conclusion that we simply can not rely on traditional plant hardiness ratings in our changing climate.

On inspiration and irrigation

Article by Judie Steeves, Past-President OXA

Take inspiration and caution from Mother Nature

Consider taking inspiration for your own landscape from Mother Nature, as well as learning about cautions to be aware of.

For instance, I recently spent a few days hiking in Manning Park, where we visited wildflower meadows in the alpine and hiked all along the string of lakes about the same elevation as Highway 3, where the campgrounds are. That’s about 1,200 metres or 4,000 feet in elevation.

I’ve hiked there in the past, and never have I seen such dry conditions in the alpine and subalpine meadows (except where there are creeks or seeps). If it’s that dry at such a high elevation, far less water than normal is coming down into the Okanagan Valley or being stored in the hills around it.

With that in mind, it would be irresponsible for us to water our home landscapes this year as much as we might in a normal summer. And, that means the plants which prefer a coastal climate or higher natural precipitation, are not going to be happy and may even die back. The plants that will thrive are the ones that naturally do well in a more-arid climate such as the Okanagan’s near-desert conditions. Check our plant database for drought-tolerant plants.

Despite drought conditions in the park, the wildflowers were diverse and beautiful and inspired me to consider replicating some of the colour combinations in my own garden.

In the alpine, at 5-6,000 feet, red paintbrush were bright against the background of silvery pussytoes and white star-flowered sandworts. A great combination! Add in the occasional deep blue of lupines or self-heal and bright yellow buttercups it was different again. Western anemone had finished flowering but their mop top seedheads were graceful and fun and reminded me of the Pulsatilla vulgaris or Prairie Crocus from my own garden, which also have seedheads that look like bedheads.

The wildflowers were entirely different on our hike along the chain of lakes at about 4,000 feet: Lightning, Flash, Strike and Thunder. It’s a more-shaded hike, with lots of creeks and seeps, wetlands and streams, so it features plants which require more moisture than we typically find naturally in the Okanagan.

However, we can substitute drought-tolerant, xeriscape plants for some of those dramatic combinations I found on the lakes trail.

For instance, there was one meadow of deep blue Upland Larkspur, nearly as tall as me, along with creamy Cowparsnip, Fireweed and thistles and I thought of alternatives such as the tall hollyhocks, Beebalm, asters and yarrow, with Fallugia paradoxa or Apache Plume. It’s a shrub of about four feet that has fluffy, pinkish seed heads in summer. All of those are tolerant of both heat and dry conditions and make a glorious show of colour and height and texture.

Paintbrush was a feature everywhere you looked, whether short or tall, and in all shades of red, orange and pink or white. However, it’s one wildflower that’s best left in the wild as it is semi-parasitic on the roots of particular grasses and won’t survive on its own.

Never dig up wildflowers in the wild. Instead, look for cousins in nurseries or explore the native plant section.

Hiking around the Okanagan is a wonderful opportunity to bring home inspiration for your own landscapes, as well as a reminder that it is very dry out there.

If we try to garden as if that natural condition did not exist, we’ll use far more water than we can afford to waste on our landscapes. If we want to live in the Okanagan, we must reform our bad habit of growing plants which require lots of water to thrive.

Gardening with Nature

Article by Sigrie Kendrick

Use native plants to help stabilize slopes

It’s just common sense to look to Mother Nature for advice about solving natural concerns on your landscape, like water, steep slopes and sun exposure or shade.

If recent rain sent a torrent of water sluicing down a steep slope on your property, leaving behind a small creek bed full of rocks and gravel and a pile of soil at the bottom, consider planting native and xeric trees, shrubs, grasses and ground covers which will naturally help to stabilize the slope.

Many residential properties throughout the Okanagan have to deal with steep slopes. Our silty soils are notorious for losing stability when exposed to higher-than-normal volumes of water such as intense rainfalls or a sudden rush of water from water line breaks or leaks.

Josh Smith, a director of the Okanagan Xeriscape Association and manager of XEN Xeriscape Endemic Nursery in West Kelowna explains that a cost-effective, low-maintenance and eco-friendly solution is to take advantage of Mother Nature’s suggestions: plant strong-rooted native and xeriscape plants that are adapted to survive and thrive on our slopes—and in our dry environment—to retain the soil and beautify the space.

Plants just after planting to help stabilize a slope on a residential property in Kelowna last year

Developing a naturalized slope-retention system on your property can take several seasons of monitoring but once it is established, it should require zero maintenance, irrigation, or upkeep.

Some key points for getting started include:

• Control the weeds until the trees, shrubs, grasses or ground covers get established. Some invasive species in the Okanagan are virulent enough to take over a slope and hinder the growth of shrubs and trees you have planted or which seed themselves.
• Grass blends or ground-cover are necessary to occlude weeds and provide surface erosion protection. These species help retain the top 10 to 20 cm of the soil.
• Tree and shrub species are what will provide deep, long-lasting, structural support to help stabilize the slope over the long term.

Smith recommends that if you are choosing plant species for slope retention or naturalized areas, go for a walk in your neighbourhood and look carefully at what is growing on natural slopes in your area. This is a surefire way to ensure you select species suited to your soil and moisture conditions.

A year later, the native plants used to stabilize the slope including a yellow-flowered sedum, grey rabbitbrush, nodding onion, a showy fleabane, kinnikinnick and native grass mix are filling in nicely

Resources

There are many wonderful resources available to help you identify native species and learn more about their growth characteristics. Phone apps like iNaturalist and Seek can help you identify plants. There are also several Okanagan-specific plant identification books, including Trees, Shrubs and Flowers to Know in B.C. by C.P. Lyons, and Plants of Southern Interior B.C. by Parish, Coupe and Lloyd, or you can take photos. They can help you look up the plant characteristics in books or on the Internet. You can also take your photos to a native plant nursery for an expert to help you identify the plant.

OXA has an extensive plant database of ornamental and native species. 

There are also specialized native plant nurseries like XEN in West Kelowna and Sagebrush Nursery in Oliver, and many other nurseries carry a selection of native and xeric species.

Sigrie Kendrick is a Master Gardener and Executive-Director of the Okanagan Xeriscape Association. She can be reached at 778-363-8360 or by email at exec_dir@okanaganxeriscape.org.

Gardening with Nature

Article by Sigrie Kendrick

Keep vital pollinators thriving with your plant choices

Pollinators have great access to food during the summer months when there is a buffet of flowers
blooming on every corner and in every meadow—but what about food for them in early spring and late
fall?

We need to make plant choices for our landscapes that are focused on extending the seasonal banquet
table for these vital little critters by choosing pollinator-friendly plants that provide food for them on the
shoulders of summer.

That should include both native and non-native xeric plants which will require little supplemental irrigation
once established, so we’re not wasting any of our precious resource, water.

It’s estimated that 90 percent of flowering plants need pollinators such as bees and butterflies to
reproduce. That includes a third of the food we eat, such as nuts, fruit, vegetables, and herbs that require
insect pollination.

As we pave over wild lands and build on meadows, we destroy natural habitat and food for pollinators, so
it’s essential that we pay more attention to planting food sources to keep these little insects alive and
thriving and reverse the current trend of their decline.

Recently the Okanagan Xeriscape Association collaborated with Kelowna Rotary Clubs on the creation
of two pollinator gardens located at Sarsons Beach Park, 4398 Hobson Rd. and Cameron Park, 2345
Richter St. in Kelowna.

These gardens have been a year in the making and it was fantastic to finally get shovels in the ground as
OXA, Rotary, and Kelowna’s Parks Department worked together to design and ultimately plant up these
spaces.

Both were designed to have both early and late-blooming perennials to support longer access to food for
pollinators.

Early bloomers in the gardens are the shrub Amelanchier alnifolia, commonly known as Saskatoon berry,
Corsican violets and the native Penstemon fruiticosus or Shrubby Penstemon.

We also included several Achillea millefolium, known commonly as Yarrow, as studies from Simon Fraser
University have shown that this perennial, which is native to the Okanagan, is by far the most appealing
to the largest number of pollinators.

Achillea millefolium will be visited by Hairy Belly Bees, Sweat Bees, Mining Bees, Butterflies, Flies,
Wasps, and Beetles.

With prompt removal of the blooms, we should get 3 bloom periods from the Achillea millefolium as well
as the Nepeta racemosa that we planted. It’s a standout pollinator perennial.

Blooming later in the season, Asclepias speciosa, Showy Milkweed, will support Monarch butterflies as
this perennial is a host plant for females to lay their eggs.

The exceptionally long-blooming Colorado Gold Gazania and Coronado Red Hyssop will round out the
season, blooming until frost.

All of the plants selected were purchased from responsible growers as many nursery plants have been
treated with toxic insecticides, known as neo-nicotinoids, which are harmful to pollinators.

Pollinator Corridor

Rotary Clubs of Kelowna have partnered with Rotary Clubs across the B.C. Interior to establish a
pollinator corridor stretching from Clearwater to Osoyoos to support the growth in populations of bees,
butterflies and other pollinators in our valley.

Visit these public gardens to see the bee-friendly gardens in person and consider planting a pollinator
garden in your own backyard to provide support for these little heroes, who are suffering from the
effects of pollution and climate change.

Sigrie Kendrick is a Master Gardener and Executive-Director of the Okanagan Xeriscape Association. She can be reached at 778-363-8360 or by email at exec_dir@okanaganxeriscape.org.

Gardening with Nature

Article by Sigrie Kendrick

Can we make better choices?

Next to our vital agricultural industry, outdoor landscapes in the Okanagan suck up the most
water.

And there’s no comparison when you consider which use is the most important: we can no
more do without food than we can do without water.

Unfortunately, the Okanagan is a near-desert and water is in short supply, a situation made
much worse by climate change and the resulting extremes in weather such as drought.

While attitudes are changing, wholesale buy-in from civic authorities, the development
community, landscape professionals and nurseries, as well as those of us who plant and water
our gardens and outdoor living spaces is absolutely essential.

No longer can we afford to be so irresponsible as to use plants that require large quantities of
water to stay alive.

With that in mind, the Okanagan Xeriscape Association has joined forces with the Okanagan
Basin Water Board, an entity on which every taxpayer in the region has representation, and its
Okanagan WaterWise program to help educate the whole community about the importance of
replacing water-thirsty landscapes with beautiful ones that require far less water.

When we obliterate natural landscapes to create buildings, and pave our grasslands and forests
over with concrete and asphalt, we simply must re-plant at least some of that with native-type
plants which don’t require large quantities of water to stay alive.

Rewilding

When we obliterate natural landscapes to create buildings and pave our grasslands and forests
over with concrete and asphalt, we simply must re-plant at least some of that with native-type
plants which don’t require large quantities of water to stay alive.

Re-wilding is the term for restoring healthy ecosystems in the landscape that have been
disturbed by humans. Think of the millions of acres of mono-culture that is turf grass currently
planted across this country.

Re-wilding aims to reverse biodiversity loss by using native plants and animal life to rebuild
ecosystems and mitigate climate change.

It is in the hope that we as humans can undo some of the destruction we have wreaked on our
home—earth.

Please consider allocating a portion of your garden to native plants.

Plants native to the Okanagan thrive in our semi-arid valley and support countless pollinators,
birds, and animals. Think of the ripple effect, much as that from a single stone thrown into a
pond.

It’s simplistic to believe that because the bottom of our Okanagan Valley features a sparkling
blue lake, water is not scarce. As soon as we begin to ‘mine’ the lake— use more water than is
replaced by natural precipitation each year— we are in big trouble.

The alternative is for all of us to wake up and give our heads a shake; to enact legislation
requiring that new developments install landscapes that use the principles of xeriscape; to insist
as creators of subdivisions, as home builders and homeowners that our landscapes use
drought-tolerant plants instead of lawn grasses, trees, shrubs and flowers that belong in a
coastal rainforest.

We have to move away from inappropriate landscape choices such as turf grass, cedar hedges
and inappropriate plant selections and instead move toward choices that better mimic our
stunning natural Okanagan environment and support our pollinators, birds, and small mammals.

We humans have to relinquish our control issues and let nature do what she does best— heal.

Sigrie Kendrick is a Master Gardener and Executive-Director of the Okanagan Xeriscape Association. She can be reached at 778-363-8360 or by email at exec_dir@okanaganxeriscape.org.