Category:

A Clematis Primer

21/7/2016

Bev Werbowy

What a pleasure to share a Guest Post by Bev Werbowy. A talented gardener and long-time member of the Thunder Bay Horticultural Society, Bev is known for her interest in alpine plants, rocks and the interplay of plant textures and hues. Her sweetly compact city garden was part of the 2015 Thunder Bay Art Gallery Garden Tour.

This article first appeared in the Spring 2016 issue of Bay Leaves, the Thunder Bay Horticultural Society newsletter. You may want to keep this post for reference. Republished with permission.
Thank you, Bev.

What can provide more pleasure, early in the season, than making the rounds of the nurseries and big-box stores to source out new plant varieties and old favourites. Time and time again, however, I find myself asking the same two questions:
Why are we seeing the same clematis varieties year after year?
Why are so many offered which are not guaranteed to survive in our Zone 3 gardens?

We have all, at some time, been seduced by those stunning large-flowered hybrids, resplendent in their jewel-toned hues, only to witness their inevitable decline in later years.

A knowledge of the specific pruning needs of the many species of Clematis will determine which we should plant and which we should avoid. The genus Clematis can be divided into 3 distinct groups based on the aforementioned pruning requirements. They are generally referred to as Group A (Group 1), Group B (Group 2) and Group C (Group 3).

Group A (1) Clematis

small flowers - generally bell-shaped
vigorous growers
bloom in early summer
bloom on wood produced the previous year
minimal, if any, pruning is required
Clematis a!pina and Clematis macropetala are very hardy, vigorous performers

Notable Clematis alpina cultivars

'Pamela Jackman - deep blue
'Frances Rivis' - violet-blue
'Willy' - pale pink
'Markham's Pink' - plum-pink
'Ruby' - pinkish-red
'Frankie' - mid-blue
'Constance' - deep pink
'Pink Flamingo' - red-purple to pale pink

Notable Clematis macropetala cultivars

'Blue Bird' - purple-blue
'Rosy O'Grady' - mauve-pink
'White Swan' - double white

Clematis alpina 'Pamela Jackman'
Photo: Royal Horticultural Society

Clematis alpina 'Markham's Pink'
Photo: Royal Horticultural Society

Group B (2) Clematis

large-flowered hybrids, single and double
bloom in early summer and occasionally re-bloom in late summer
flower on previous year's growth

This group is the least reliable and should be avoided. Some examples are:

'Duchess of Edinborouqh'
'Multi Blue'
'Dr. Ruppel'
'Henryi'
'The President'
'Elsa Spath'
'Niobe'
'Nelly Moser'
'H.F. Young'

You will recognize several of the above selections since they regularly appear of big-box stores and some nurseries. Do not be tempted!

Group C (3) Clematis

includes both large and small-flowering cultivars
bloom in late summer on new wood
prune back to twelve inches in early spring

Recommended large-flowered hybrids

'Comtesse de Bouchaud' - mauve-pink
'Rouge Cardinal' - crimson-red
'Ville de Lyon' - carmine-red
'Pink Fantasy' - pale pink/ darker bar
'Jackmanii' - purple

Recommended small-flowered hybrids

'Alba Luxuricrns' - green-white
'Abundance '- deep red
'Etoile Violette' - dark purple
'Huldine' - white
'Margot Koster' - mauve-pink
'Minuet' - mauve-green
'Mme. Julia Correvon' - red
'Purpurea Plena Elegans' - red-maroon
'Venoso Violocea' - purple-white

The Clematis viticella hybrids, also members of Group C (3), perform reliably in Zone 3. What they may lack in flower size, they more than make up for by their profusion of bloom. Their flowers come in a variety of forms; open-faced, bell-shaped, rosette and recurvate, They will happily clothe a trellis or scramble through shrubs.

'Polish Spirit' is one of a group of hybrids bred by Brother Stefan Franczak, a Jesuit priest from Warsaw. Other notable examples of Polish Clematis in Group C (3) are 'Warsaw Nike', 'Danuta' and 'Kordynol Wyszyriski'.

Mention should also be made of Clematis integrifolia 'Arabella'. Purple-blue, this plant is very vigorous, a great scrambler.

Clematis recta 'Purpurea' – a herbaceous clematis whose leaves emerge sporting a lovely purple-burgundy colour. They will retain this hue until the small white flower clusters emerge. I train this plant up a small
obelisk, thereby providing a striking exclamation point in the perennial border.

The well-known Clematis tangutica is a prolific climber (up to 4m). It produces small yellow, cup-shaped flowers.

Final thoughts ...

Check the pruning group before purchasing. lf it's not on the tag, Google the cultivar first.

Avoid Group B (2). • lf you must succumb to Group B envy, try 'Guernsey Cream'. lt has survived in my garden for five years ... by keeping my fingers crossed (and the ground mulched)!

Clematis 'Rouge Cardinal'
Photo: Royal Horticultural Society

Clematis 'Polish Spirit'
Photo: Royal Horticultural Society

Clematis recta 'Purpurea'
Photo: Royal Horticultural Society

Want to learn more?
Most of the cultivars mentioned are profiled on the Royal Horticultural Society online plant guide. It is an excellent compendium of plant information, but always confirm the Canadian hardiness of plants to be sure of success in our colder zone.

Comments

My Garden 2.0 - Straw Bale Update #1

31/5/2015

Comments

The straw bales that will become my veggie patch for this season are beautifully spongy, speckled with bacterial growth and sprouting the odd mushroom. In other words, they are nearly perfect for planting. I've been monitoring things daily, planning to apply a balanced fertilizer as the final pre-planting input. I was not able to locate 10-10-10 fertilizer, but I did find organically-based fertilizer at a local nursery with an N-P-K mix of 5-10-5, which is a good all-purpose ratio. Today I applied 1/2 cup to each bale and watered in well. Now, all we need is sunshine and warm days.

What does the N-P-K ratio mean?
The three numbers that appear on fertilizer packages (N-P-K) reflect the ratio of nitrogen (N), phosphorus (P) and potassium (K) which are the nutrients plants need in large quantities. Generally we say that nitrogen is for leaves, phosphorus is for roots and potassium is for fruits. A fertilizer for your lawn will have a high nitrogen content – say 20-5-5 – to promote leaf growth. A fertilizer formulated without nitrogen – say 0-10-10 – is meant to promote the setting of flowers and fruits.

When to plant?
This is the million-dollar question, especially in a Zone 2/3 area where spring frosts are a concern. Here were are on the eve of June 1st and they are calling for nighttime temperatures of -2 degrees. Experienced gardeners in my part of Ontario wait until after the first full moon in June to plant tender vegetable starts like tomatoes and squash. According to the Canadian Almanac, the full moon will fall on June 2, just days away.

See that lovely tomato plant in the photo? It's a patio tomato that should produce lots of medium- sized fruit. But I am keeping it indoors tonight! And so, the straw bale experiment continues ...

Did you know ...?
The full moon in June is called the Strawberry Moon.
Are you planting a vegetable garden this year?
Have you planted already? What are you growing? Leave a comment to share your plans.

Comments

A hardy tree for tomorrow

2/5/2014

Comments

"Large streams from little fountains flow, Tall oaks from little acorns grow."
― D Everett, The Columbian Orator, 1797

PHOTO: Mark Hirsch, Bur oak that inspired 'That Tree' iPhone photo project ― http://thattree.net/

Trees are a necessity for the human soul. Trees give us health, beauty and cool respite. They give us a sense of place and they teach us about the passage of time. If we were wise, we would plant many more trees than we do, for every newly-planted tree contributes to the renewal of our shared landscape.

I learned to love trees first from my mother and later from the foresters I've come to know in Northwestern Ontario. The passion of tree developers like Rick Durand of Bylands Nursery in BC have also inspired me to value trees. A well-tended tree may well grow to be the soul of a garden.

Lest you think this will be a wholly poetic post, let's shift gears and talk about trees that can withstand the harsh weather of a northern garden. Happily, there are many species that will give us shade, form and privacy.

Young bur oak growing in an open setting, Calgary

One of my favorite trees is bur oak (Quercus macrocarpa). It is pictured above in its happiest setting – growing out in the open in a grassy space, which is the modern equivalent of its natural prairie habitat.

Could you grow a bur oak in your yard? Absolutely! As a specimen tree that gives shade and character in the urban landscape, I think it is a fine choice.

Bur oak (also spelled burr oak) is a small to medium sized deciduous tree that can grow 15 to 20 m (50 to 65 ft) tall. It is considered a slow-growing tree, but once established it will adapt to dry and moist conditions. As the Manitoba Forestry Association explain in the Think Trees seedling catalogue, "A deep & wide-spreading root system with a strong taproot makes this species drought-tolerant." This makes bur oak a good choice if you are establishing a moisture-conserving landscape.

Remember that 'sense of place' I mentioned? Bur oak is very long-lived, surviving up to 200 years, given care and good growing conditions. There is no doubt a bur oak is a heritage tree worth planting for future generations.

Oaks are divided into two groups: red and white, based largely on the appearance of the leaves and acorns. Bur oak belongs to the white oak family with the characteristic lobed leaf shape. The leaves have a paler underside that is covered with short fine hairs. Leaves turn a tawny brown in fall.

Like other white oaks, the acorns of the bur oak mature in one year. In fact, it's the bur oak acorn that is especially distinctive. The fringed acorn caps give this tree its other name – mossy-cup oak.

Bur oak is noted for its heavily fringed acorn cups

We planted a bur oak some years ago. Now, about five years on, it is developing the gnarly branches that give this tree its character.

Bright green leaves have deep rounded lobes

Gnarly branches

In a brief paper by Mary Ann Riley (Kemptville College), I learned that "bur oak grows best on deep, dry, rich bottom lands. Its preference is for well drained sandy or clay loam soils. It also occurs on upland limestone soils and at the northern limits of its range, on shallow soil over granite bedrock. Trees may be stunted on exposed shallow soils." Now this sounds like northern Ontario, doesn't it? We count on tenacious trees, even if they do get gnarly.

So let's summarize ...

Bur Oak

Size: 15 to 30 m tall, trunk 60-120 cm diam
Moisture: Tolerates a wide variety of moisture conditions
Exposure: Prefers full sun, but can tolerate moderate shade
Soil: Can grow in a variety of soils
Form: Short trunk with a wide crown when open grown
Bark: Thick, dark grey bark, deeply furrowed
Zone: 2b

As we step towards Arbor Week, why not think about trees. Maybe a bur oak is the tree for your yard. Now – while trees are dormant – is the best time to plant. Where could you plant a tree?

Want to learn more?
For reliable tree planting tips check out the Ministry of Natural Resources' Climate Change pages.
Read more about 'That Tree' iPhone Photo Project
Photo credits:
Open grown specimen, Calgary - Flora and Fauna [blog]
Leaves, acorns, branches - Peter M. Dziuk at Minnesota Wildflowers
Fall leaves - The Dirt Doctor

Comments

How cold is too cold?

5/1/2014

Comments

We're in the grip of deep and numbing cold in Northwestern Ontario. Each day as I wince at the thermometer reading, I wonder 'how cold is too cold' when it comes to our plants, shrubs and trees?

There's good news and bad news.

Around the northwest region, most perennials are safely covered with plenty of snow. Snow is the great insulator. It keeps the ground from freezing too deeply and damaging roots. Plants that are hardy for Zones 2-3 should survive.

That's the good news.

Shrubs and trees, on the other hand, are more at risk of winter damage. I am thinking of landscape specimens we plant in our gardens and around our house foundations rather than the hardy native species that grow in the forests of our region.

Tree showing breakage from heavy snow.

Recent reports of ice damage to trees in southern Ontario have been heartbreaking. The heavy weight of ice and snow can flatten shrubs and bend or break the limbs of deciduous trees. Ice makes branches brittle which means removing ice can break branches. It's best to leave them alone. Snow on the other hand can be removed from shrubs and smaller trees with a broom by pushing the broom in an upward motion.

Evergreens are also susceptible to damage. "Sunny days in winter, or wind, can cause evergreen leaves to lose water or 'transpire'," says Dr. Leonard Perry, at the University of Vermont. "Since the ground is frozen, roots can’t take up replacement water, so the result is the leaves drying out and browning." The winter-scorched needles will eventually drop off.

Euonymous showing signs of winter scorch

Broadleaf evergreens such as euonymous (Euonymus fortunei) and rhododendron can also be affected by scorch.

According to Dave Clement, a plant specialist at the University of Maryland, "Leaves curl and droop, then brown from the tips and margins, giving the leaves a scorched appearance. In many cases damage occurs during the winter months but symptoms appear in the spring as the plant begins to emerge from the winter dormant period and move into the spring growth phase."

This is all bad news, indeed.

What can we do to protect shrubs and trees from winter damage? Like so much in the garden, being proactive is key.

Tips for Winter Protection

Plant varieties that are hardy for your zone.

Plant shrubs and perennials where they are protected from cold wind.
A fence, evergreen hedge or structures can provide a windbreak.

Add a layer of mulch.
After the first freeze, additional mulch will reduce water loss from the soil and reduce the heaving that occurs as the soil freezes and thaws in late autumn.
Stop feeding plants quickly-available nitrogen in late summer.
Let them harden off – slow their growth – before cold weather sets in.
Water deeply.
Ensure shrubs and trees – all plants – receive plenty of water in the soil so that their tissues are well hydrated going into the winter.
Make use of snow.
As snow arrives, if it is not too heavy, gently shovel it in and around shrubs. This is especially helpful for broadleaf evergreens. Even the euonymous on the north side of our house survive when tucked in with the white stuff!

Photo credits:
Thermometer - therebloomsagarden.com
Snow damaged tree - University of Maryland Extension
Euonymous - Viette Nurseries

Want to read a little more?
Understanding winter hardiness
Growing azaleas and rhododendrons in the north

Comments

Black beauty

29/9/2013

Comments

A dark, mysterious beauty appeared in my garden this summer. What was this unexpected and lovely flower?

Tall Bearded Iris 'Suspicion'

It was a dramatic black-purple Tall Bearded Iris aptly named 'Suspicion'. This iris was tall indeed (60-90 cm), standing well above companion iris and demanding every garden visitor's attention.

Well, isn't it a beauty, looking so fresh-faced after a rain?

We all have plants with sentimental histories. The iris was a gift from a friend who was leaving the community and for that reason I feel a special attachment. This black beauty did not bloom last year, making its return all the more sweet.

As I have since learned, 'Suspicion' was hybridized by Schreiner's Iris Gardens in Oregon's Willamette Valley and introduced in 1977. It's a mid-season bloom.

Some may not consider my iris "black" enough, although I think it holds its own against the three dark cultivars pictured below.

'All Night Long'

'Hollywood Nights'

'Black Tie Affair'

'All Night Long' is a cross of 'Hollywood Nights' and 'Black Tie Affair'. According to Schriener's online catalogue, "The intensity of this purple-black color and the vibrancy of its undulating ruffles provide 'All Night Long' with an energizing garden presence." It does have a certain elegance.

The appearance of my dark beauty got me thinking about black flowers. It is said that there are no truly black flowers; that in fact, natural black flowers are a deep, dark red or purple; it's their rich pigmentation that makes them appear nearly black.

The black flower has been a source of fascination – even obsession – for plant collectors and breeders for generations. In the Victorian era, collectors returned from the farthest corners of Asia and South America with exotic new plant species. Those with dark blooms were much desired. As the fascination for black flowers grew, Victorians developed entire gardens dedicated to dark flowers and foliage. Garden writer Nikki Phipps offers a fairly thorough list of plants for recreating a Victorian black garden, if you are so inclined.

Funny that in gardening, as in many other things, what's old is new again. Dark blooming plants and dark foliage are trendy at the moment. Trends don't persuade me, although I admit that I find rich burgundy foliage very attractive and well suited to my garden.

Euphorbia dulcis 'Chameleon'

I was delighted when a friend gave me a small pot of
Euphorbia dulcis 'Chameleon'. This lovely spurge adds mystery and character to a mixed perennial bed. I hope it will prove as hardy as my old stand-by Euphorbia polychroma (Cushion Spurge).

I agree with Nikki Phipps' advice to place dark-colored plants in sunny areas or "against a lighter backdrop in order to stand out more effectively." Plants with light foliage and flowers make a wonderful foil for the darkest blooms.

Memories of my black iris linger still. So glad I photographed her mysterious dark self. She will – I hope – come again next year.

Photo credits:
Bearded Iris 'Suspicion' - There Blooms a Garden
Iris cultivars - Schreiner's Iris Gardens
Euphorbia dulcis 'Chameleon' - Bailey Nurseries via Fine Gardening Plant Guide

Comments

<<Previous

A Clematis Primer

My Garden 2.0 - Straw Bale Update #1

A hardy tree for tomorrow

How cold is too cold?

Black beauty

Categories