Flowers' blooms an unrivalled spectacle

Who can resist a beautiful begonia? At the height of summer, the luxurious blooms provide an unrivalled spectacle. Few gardeners ever plant just one begonia and most of us have a favourite type of begonia or even a particular variety that we like to grow each year in our gardens.

The genus begonia contains more than 1,700 different species. Depending on the type of display you want to create, style or size of container, and where you are placing begonias in the landscape, begonias come in a multitude of shapes and forms. Choose from shade lovers such as flowering tuberous begonias or leafy Rex begonias or sun-tolerant wax or fibrous begonias as well as an exciting range of heat-tolerant Begonia boliviensis varieties with masses of pendulous blooms.

In recent years, breeding breakthroughs have introduced sun-tolerant hiemalis begonias such as the Solenia begonia with fully double, continuous blooms that are semi-trailing. Hiemalis-type begonias, also known as rieger, represent a cross between a tuberous and a wax begonia. Sometimes called elatior, these types can offer a more upright habit with dense bouquet-type clusters of dainty blooms.

This spring, gardeners will notice the absence of certain familiar and well-loved begonia varieties. To understand why, let’s take a step back to last December when the presence of a bacterial leaf spot (Xanthomonas) was detected on begonia mother stock at the production facility of a major begonia breeder. Bacterial leaf spot is a serious foliar disease characterized by foliar lesions and wilting resulting in the death of leaf tissue.

Once identified, the impact was immediate. The highly reputable breeder opted to take the high road and ceased the shipping of begonias to their North American customers despite the fact that the disease was detected on less than three per cent of the begonia mother stock. This extraordinary step was taken out of an abundance of caution as the disease can spread to healthy plant material. The disease was quickly contained and all affected stock destroyed.

Since the affected begonia varieties are among some of the most unique begonias available on today’s market and include vegetatively propagated types such as Solenia begonia and my very favourite, Unbelievable Miss Montreal, the loss has also been felt by local greenhouse growers who scrambled in the past few months to find substitutes in time for spring. Fortunately, their efforts have been rewarded and there are many different begonia varieties that will still be available, including some intriguing new introductions.

Funky Pink, says Diane Whitby, owner of Red Valley Plant Market, is a floriferous trailing begonia with large, deep pink double blooms. It’s, well, funky. The layers of slender pink petals are brushed lightly with threads of gold radiating from a softly ruffled centre for a unique colour combination. An interspecific cross of Begonia boliviensis and Begonia tuberosa, Funky Pink has olive green toothed foliage. This pretty begonia with its dangling flowers is well suited to hanging baskets or tall containers. It thrives in full morning sun and benefits from dappled light in the afternoon.

California Sunlight is a mounded, semi-upright Begonia boliviensis ­variety that has, in my opinion, a distinct resemblance to another Begonia boliviensis of a few years ago — Sparks Will Fly. Featuring similar five-petalled, bell-shaped flowers in vibrant tangerine-orange against contrasting dark foliage, California Sunlight is a dense, compact plant loaded with single blooms.

Whitby also likes Fiery Orange, a compact, mounded Boliviensis cross with semi-double blooms. Both California Sunlight and Fiery orange can go in partial sun providing they receive some protection from the hot afternoon sun. California Sunlight, which is also shade tolerant, will provide a spark of tropical colour to shade containers.

Hanging varieties of Begonia boliviensis that you will be able to find this spring include the Mistral and Belleconia series.

Love the old-school look of large, fully double tuberous begonias with their layer upon silky layer of petals in rounded blooms? Nonstop Mocca Mix is a type of tuberous begonia (Begonia x tuberhybrida) that provides a mix of blooms in five colours — red, dark red, orange, yellow and white — and contrasts the seven-to-10-centimetre blooms with unique chocolate-purple foliage with grey-purple veins. Too beautiful.

Suited to a part-shade to shade location, Whitby says that Nonstop Mocca Mix will tolerate more sun than traditional non-stop begonia varieties. Tuberous begonias can be lifted prior to the first frost, and stored for the winter. They are also, however, more susceptible to fungal diseases such as mildew. Avoid overhead watering and provide good air circulation.

Summerwings Ebony and Orange, available at Lacoste Garden Centre this spring, is a mounded tuberous begonia. Foliage is dark green to near-black. Jensen’s Nursery plans to carry Summerwings Dark Elegance, Pink Elegance and Vanilla. "Summerwings will go in full sun," Sue Jensen Stubbe says. Gradually acclimatize any sun-tolerant begonia before moving it from a protected greenhouse environment into a part-sun to full-sun location.

A distinct advantage of hiemalis begonias, commonly known as rieger or elatior-type of begonias, is that they have been bred for mildew-resistance, wind-resistance and sun-tolerance. When Solenia begonia first came onto the scene, it represented a game changer for gardeners. Although available in limited supply this spring, Stewart McLeod, of Lacoste Garden Centre, says that he will have Solenia Dark Pink, Light Pink, Red Orange, Velvet Red and Light Yellow.

Dragone Champagne, another hiemalis begonia, has a pretty bouquet-type form that is perfect as a filler at the front of containers. I grew Dragone Sunset a few years ago and loved the dainty salmon-coloured flower clusters. Dragone Champagne has softly coloured shell-pink flowers and dark foliage with pointy tips.

Another variety to try this spring is Betulia begonia, a brand new introduction from well-known begonia breeder Koppe in the Netherlands. A hiemalis begonia with a round growth habit, dark foliage, and semi-double to double blooms, Betulia has a medium sun tolerance so should be protected from the hot afternoon sun. Both Dragone Champagne and Betulia will be available at Red Valley Plant Market.

I’m in love with Rex — Rex begonia, that is. A type of rhizomatous begonia, Rex begonias are grown for their highly decorative leaf shapes, unusual colour combinations and often distinctive, deeply cut patterns. Perfect for areas of the garden with low light levels, these show-stopping foliage plants are easy to grow.

Shea Doherty, of Our Farm Greenhouse in Portage la Prairie, shares my passion for Rex begonia and will have more than 20 different varieties this spring.

"The performance of Rex begonia in the shade garden, as well as how the foliage presents in the fall, makes it a multi-purpose plant," says Doherty, whose enthusiasm is contagious. I can’t wait to grow Paso Doble, a Rex begonia with tightly frilled dark purple edges bordered by brilliant green that surrounds a splash of watermelon red and an escargot-like swirl in the leaf centre.

Doherty has numerous other fabulous begonia selections, but alas, I have run out of space. I will find plenty of space in my garden, though.

It may be a summer without some of our favourite begonia varieties, but perhaps the silver lining is that we will discover new ones. Be assured that your old favourites will return, better than ever.

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