Overwintering Rieger Begonias

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Rieger begonias. Photo: http://www.swflorist.com

Rieger begonias (B. × hiemalis), often called Elatior begonias, are hybrid begonias, originally derived from a cross between summer-flowering tuberous begonias (B. × tuberhybrida) and a rarely cultivated winter-flowering species, B. socotrana starting as far back as 1883. The name Rieger, now applied to all of them, comes a series introduced in 1955 from German hybridizer Otto Rieger. The alternate name, Elatior begonia, likewise derives from a once popular strain otherwise largely forgotten.

Begonia ‘Valentino Pink’, with its original cluster of yellow staminodes, has been enormously popular in my area. Photo: http://www.jenptenhave.nl

Originally, Rieger begonias were winter-flowering (that’s what hiemalis means!), needing short days in order to bloom, and they were, in fact, commonly called winter begonias. But over time, everblooming begonia species were added to the hybridization palette and most modern hybrids, like the Solenia, Valentine, Dragone, Frivola and Glory series, are day-neutral and essentially everblooming.

Due to their original winter blooming habit, they were first grown as houseplants, often for the Christmas market, but the modern hybrids capable of bloom all summer long have now transitioned into a new role as garden plants, although they still do fine indoors and are commonly sold as gift plants for indoor use during the winter months.

Some Rieger begonias trail somewhat and can be used in hanging baskets. Photo: http://www.scottstreetgreenhouses.ca

Rieger begonias are densely clustered plants producing multiple stems. Some have a mounding habit, while others tend to be trailing and are better suited to hanging baskets. Plants typically measure about 10 to 18 inches (25 to 45 cm) tall and wide. The shiny, rounded to heart-shaped leaves are green or bronze. The flowers can be single, semi-double or double; the double ones often look a lot like roses. The flowers are of a variable size: typically about 1 inch (2.5 cm) in diameter, although some, like those in the Solenia series, are up to 3 inches (7.5 cm) wide, almost as large as some tuberous begonias (B. × tuberhybrida). They come in a nearly full range of colors: red, pink, white, orange, purple, etc.; only blue is missing. They’ll bloom non-stop for months at a time, usually until well into fall if purchased in the spring. No wonder they’re becoming so popular!

Overwintering Is a Problem

The Solenia series (here Solena Yellow Improved) has extra large blooms. Photo: http://www.provenwinners.com

The problem with Rieger begonias is overwintering them. Not that nurserymen are much concerned. “They’re annuals,” they insist. “Let them freeze!” Yes, a non-plantperson would say that. But they aren’t annuals, they’re subtropical perennials. If you’re like me, you won’t want to give up on any plant that is salvageable. 

The difficulty is that Rieger begonias have retained a genetic disposition to going dormant in the fall, a trait inherited from their tuberous parents, yet they don’t produce any tubers to go dormant into. So, if they do die back to the state of full dormancy, they simply end up dead, certainly not what you want!

Rieger begonias can be overwintered, but how to do so seems to be a secret professionals just don’t want to share with home gardeners. Certainly, I’ve found pretty much nothing on it in gardening books or on the Web. So, I had to learn on my own, losing more Rieger begonias than I care to think of over the years. But I’ve finally got them figured out. 

Here’s what I do: 

Fall Care

Yes, cut Rieger begonias back when you bring them in. It may be harsh medicine, but it works! Photo: http://www.veldkampsflowers.com

When I bring my Rieger begonia back indoors in the fall, I cut them back harshly, about a 1 to 2 inches (3-5 cm) from their base. Yes, they’re often still in full bloom, but they seem to need a shock just before they would instinctively start to go dormant. This sudden attack seems to push them into survival mode and, instead of dying back, they start to produce new stems.

Keep them in bright light and water only moderately as new stems grow back, remembering they won’t need much water until they start producing new leaves. They seem to prefer cool temperatures (45-55°F/7-13°C) at this time. By the New Year, they should be coming back strongly. At this point, I suggest making a few backups, so cut off and root some extra stems, just in case. 3-inch (8 cm) stems root quite nicely: plant them 3 or 4 per 6- to 8-inch (15-20 cm) pot for a nice full plant.

Keep both the cuttings and the original plant fairly cool, but in the brightest light you can imagine: this is winter, after all, and sun is at a premium. You can water more generously as they begin to fill in. 

By spring, your Rieger begonias should be coming along just fine. They don’t mind a bit of shade, but indoors, at least at this season, full sun seems best. You can start fertilizing them, lightly (they’re not heavy feeders), as days grow longer. 

Soon buds appear, then flowers. And there you go: you’ve overwintered your Rieger begonias and brought them into bloom again.

Mildew

Powdery mildew on a Rieger begonia. Photo: L. Pundt, UConn

Older cultivars were quite susceptible to powdery mildew and often needed special fungicide treatments to maintain healthy leaves. Better disease resistance has been bred into today’s hybrids, but do keep them aerated and don’t overwater, just in case. If they are hit, just remove the diseased leaves and they usually fill in again rapidly.  

Outdoors

You can, of course, grow these begonias indoors all summer if you want. (Few people seem to do so anymore, but they grow really well that way.)

Rather, most people these days want them as garden plants. If so, when all risk of frost has dissipated, acclimatize them carefully to outdoor conditions (a week in shade and a week in partial shade before daring full sun). Outdoors, they prefer cooler conditions and will do best in partial shade in many climates. In my cooler summer area, they’re perfectly happy in full sun. The Solenia series was actually developed for better resistance to full sun and would be a good choice for hotter climates.

Rieger begonia back outdoors again. Photo: NetPS Plant Finder

You can grow Rieger begonias in pots or in the ground. And these are no longer the delicate “winter begonias” your grandfather grew, but are, in fact, tough, easy-to-grow plants. Just give them basic “annual flower” care and avoid overwatering. They’re pretty much sterile, almost never producing seeds, and are essentially self-cleaning, so no deadheading will be necessary.

In fall, just bring them in and start over!


Best of luck with your Rieger begonias! 

Houseplant of the Month for April 2019: the Begonia

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The Story of the Begonia

Flowering begonias have full, plump flowers in cheerful colors such as red, pink, orange, white and yellow. The enthusiasm with which the plant blooms means in practice that you can hardly see the plant for the flowers. 

Foliage begonias have their own distinctive beauty in the form of velvet leaves that are beautifully marked with silver, pink, burgundy and green patterns that more than make up for the absence of flowers. 

They’re both plants with a luxurious look, yet still surprisingly simple and easy to care for. 

Begonias fit well with the trend where plants provide a soft, friendly buffer against non-stop news updates and the harsh outside world. 

Origin

There are 1895 different species of begonia, most of which grow in warm, damp forest regions in South and Central America, Africa and southern Asia. The wild species come in all sorts of shapes and sizes, but are generally herbaceous (non-woody) plants with asymmetric leaves and numerous flowers borne on branching stalks. The flowers are monoecious; that is, there are separate male and female flowers on the same plant. Most begonias have upright or creeping stems, often with distinct nodes. Many have tubers or rhizomes.

Begonia Range 

Elatior begonia flowers and rex begonia leaves. Styling: Elize Eveleens – Klimprodukties

The begonia range is very extensive. 

The most common flowering houseplant begonia is the Rieger or Elatior begonia (Begonia × hiemalis) with single, semi-double or double flowers. One new addition is the Bodinia Line with extra full flowers and curly foliage. The Betulia line is also very suitable for use both indoors and out. 

There is even more diversity among foliage begonias. 

Rex begonias (B. × rex-cultorum) are available in various attractive leaf colors, structures and shapes. The Beleaf line has an attractive structure and eye-catching colors. 

Another popular group are the various rhizomatous begonias, including the eyelash begonia (B. bowerae), with creeping rhizomes and colorful leaves. They’re classics within the foliage range. 

And then there are the upright varieties with canelike stems, often called angelwing begonias, like B. maculata, many characterized by pink flowers and leaves with silvery-gray spots.

What to Look for When Buying Begonias 

  • Pot and plant must be in proportion, and the plant must look attractive and full.
  • With flowering begonias, there should be sufficient ripe buds visible. 
  • To be on the safe side, check whether it’s an indoor or outdoor begonia. 
  • Damaged leaves or leaves with marks indicate shipping damage, yellow leaves indicate a lack of water.
  • The plant must be free of pests and diseases. 

Care Tips 

Begonias need bright light, but not necessarily direct sun.
  • Begonias need a lot of light, but don’t like bright sunlight in the summer months.
  • Water as needed to keep the growing mix slightly moist at all times.
  • Try to avoid spraying your begonia; it can cause mildew (a fungus).
  • Removing wilted flowers can help stimulate new ones.
  • Fertilize lightly at each watering to keep blooming begonias in flower.

Showing Off Your Begonias

Rex begonia (left) and Elatior begonia (right). Styling: Elize Eveleens – Klimprodukties

The fabulous display of begonia flowers and foliage is always appealing. 

Reinforce the soft, plump appeal of Elatior begonia flowers with soft ornamental grass and plants with velvety leaves. 

Foliage begonias can be effectively displayed in different sizes to show how versatile they are. 

For both the setting should be soft and friendly: fluffy rugs, lovely cushions, planters that seem covered in fur.


Text and photos from a press release by Thejoyofplants.co.uk.

For more information on begonias, read 2016: Year of the Begonia.

2016: The Year of the Begonia

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The Begonia House at the Montreal Botanical Garden.

Each year the National Garden Bureau declares a “year of” that features four plants: one vegetable, one perennial, one annual, and for the first time in 2016, one bulb. We looked at the Year of the Carrot earlier in the month. Now let’s look at this year’s annual, the begonia. In coming weeks, I’ll look into the other two winners.

Origins

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The genus Begonia has a pantropical distribution.

With more than 1,700 species, Begonia is the fifth largest genus of flowering plants in the world, with almost an almost pantropical distribution: South and Central America, Africa, and Southeast Asia. The genus was named by the French botanist Charles Plumier for his friend, Michel Bégon, governor of the island of Saint Domingue (now Haiti) and a serious amateur botanist.

What is a Begonia?

The genus is composed of a wide range of mainy herbaceous plants (a few are semi-woody), including some with rhizomes and tubers, most adapted to moist tropical or subtropical climates. Nearly 15,000 hybrids of these popular plants exist. Although a very few species show some adaptation to temperate climates (B. grandis, for example, is hardy to zone 6b), most are grown as houseplants or as bedding plants, treated, in the latter case, as annuals in cold climates. They are also grown as perennials in hardiness zone 10 and above. Some begonias are grown mainly for their beautiful, often exotically colored foliage, others for their attractive, abundant and long-lasting flowers.

Most gardeners with a bit of experience can recognize a begonia on sight, but here are few pointers for beginners:

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    Leaves are often wing-shaped.

    The leaves are alternate and usually asymmetrical (they are often ear-shaped or wing-shaped);

  • There are usually distinct nodes (bumps) on the stem;
  • The flowers are quite distinctive, with two opposite sepals much larger than the pair of much smaller petals, borne at right angles to the sepals. This is however really only obvious with single flowers.
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    Winged ovaries

    Female flowers have a winged ovary behind their tepals. It usually has three wings.

Begonia flowers are monoecious (male and female flowers appear separately but on the same plant). Its winged ovary readily distinguishes the female flower from the male flower. If the female flower is fertilized, the ovary becomes a capsule filled with numerous very fine seeds that, in nature, are carried far and wide by the wind, ensuring the species’ survival. Many species are epiphytes and grow on tree branches or trunks.

Classification

Horticulturists like to put plants into categories, but begonias have always given both taxonomists and gardeners a hard time. After all, how can you bring order to chaos? Some botanists accept no less than 87 sections in the genus, while some horticultural classifications include dozens of groups. However, begonias, even from different continents and with different numbers of chromosomes, will often readily cross, so many plants have traits belonging to two different classes and sections and thus fall through the cracks.

Here is a simplified classification that might be useful for the ordinary gardener, although it is certainly too simple for serious begonia collectors.

A. Fibrous-rooted Begonias

This category is a bit of a misnomer: all begonias have fibrous roots. However, it is commonly used to describe all begonias that have only fibrous roots, therefore neither rhizomes nor tubers. Fibrous-rooted begonias can be short to tall and may be grown for their foliage or their flowers.

A1. Wax Begonias (B. x semperflorens-cultorum)

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Begonia x semperflorens ‘Ambassador Green Leaf’

Traditionally, this group includes only one hybrid species: B. x semperflorens-cultorum, the popular wax or bedding begonia. This is a relatively compact plant with erect stems and glossy, somewhat spoon-shaped leaves, green or bronze in color. The flowers are small but numerous, in various shades of pink, red and white.

For convenience sake, I like to include two more recent introductions in this category: so-called B. x benariensis (I’m far from sure the name is botanically valid) such as the ‘Big’ series (plants twice as large as the usual B. x semperflorens-cultorum, but otherwise very similar) and Dragon Wing and Baby Wing series, with arching stems and wing-shaped leaves.

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Begonia ‘Dragon Wing Red’ falls between the cracks: it behaves and is used like a wax begonia, but has leaves like an angel wing begonia.

These begonias are usually produced by seeds and treated as annuals, but you can also multiply them by division or stem cuttings. You can also prolong their life by moving them indoors in the fall to serve as houseplants.

A2. Other Fibrous-rooted Begonias

Typically begonia authorities divide this group into many subcategories, such cane-like begonias, shrub-like begonias, thick-stemmed begonias and trailing or scandent begonias. However so few are available through in the average garden center that I find this creates confusion rather than simplifying things, so I prefer to lump them all together into a single category.

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Fibrous begonia ‘Lucerna’: a popular hand-me-down houseplant.

Often these begonias have erect stems, although often arching at the tip, stems with very obvious knots and highly asymmetric, wing-shaped leaves (they are often simply called “angelwing begonias” for that reason), although there are many exceptions: plants with climbing or pendant stems or with leaves that are star-shaped or even compound. Their foliage is often the main attraction: it often shiny, hairy, purple, red, or dotted with silver. The flowers tend to be small and usually pink, red or white, rarely orange. Some species branch abundantly, others tend to produce few ramifications, even when you pinch them.

Usually these begonias are grown as houseplants in temperate climates, although they also do wonderfully planted outdoors for the summer. In the Tropics, they are treated as perennials or small shrubs.

Fibrous-rooted begonias are usually multiplied by stem cuttings or by division.

B. Rhizomatous Begonias

These begonias have a rhizome: a usually creeping stem (although some rhizomes are upright) that root in contact with the soil as they grow. The plants tend to get wider as they age, but to remain low growing. This category is traditionally divided into 2 parts: rhizamotous begonias per se (a sort of holdall category) and rex begonias.

B1. Rhizomatous Begonias

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Rhizomatous begonia Begonia heracleifolia nigricans is one of the rare begonias with star-shaped leaves.

This is the largest category of begonias, with hundreds of species and thousands of cultivars. Most are fairly compact plants (but there are also varieties with very large leaves), often with round or star-shaped foliage. The flowers are usually pink or white and tend to bloom during the winter, since most require short days in order to bloom. Most are mainly grown for their attractive and often very colorful foliage.

Until recently these begonias were generally considered houseplants, but gardeners have begun to discover they also make excellent annuals for shady flowerbeds.

This group is usually multiplied by stem cuttings, leaf cuttings or division.

B2. Rex Begonias

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A few examples of the variety in Begoniarex-cultorum.

This subcategory of rhizomatous begonia includes hybrids derived from the long-lost species B. rex crossed with other begonias. The resulting hybrid species is called B. x rex-cultorum. The foliage of rex begonias is particularly colorful, coming in all imaginable shades of green, red, silver, purple, brown and pink, often with metallic highlights. Originally rex begonias had leaves that were more or less ear-shaped, but there are now varieties with star-shaped and even spiral leaves. Although most have creeping rhizomes, some do have upright ones. These begonias are normally grown uniquely for their foliage and little attention is paid to their rather sparse white or pink flowers.

Rex begonias are propagated in the same ways as other rhizomatous begonias and require much the same care. They are however considered harder to grow well, especially over time. Many varieties go into a sort of semi-dormancy in the winter, losing many or most of their leaves. If so, temporarily reduce their watering, letting the soil dry out more than usual, while still maintaining good atmospheric humidity. Start watering more abundantly when the plant shows signs of new growth.

Long considered houseplants, rex begonias have begun to star in shadier parts of the summer garden in recent years.

C. Tuberous begonias

These begonias have a tuber, an underground organ much like a potato, and differ from most other begonias in that they go fully dormant for months, losing both leaves and stems.

C1. Hybrid Tuberous Begonias (B. x tuberhybrida)

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Begonia x tuberhybrida ‘Mocha NonStop’

This is the classic large-flowered tuberous begonia gardeners have salivated over for generations. Most have extremely double, extremely large flowers (up to dinner plate size!) and come in a variety of colors: pink, red, yellow, purple, white, orange, etc. Often the flowers are bi-colored or have fringed margins. The stems may be upright or drooping, the latter often used in hanging baskets. There are dozens of classifications for these begonias (Picotee, Fimbriata, Pendula, Crispa, etc.), but you don’t need to know how to classify them in order to grow them!

The very popular ‘NonStop’ series, used extensively in flowerbeds worldwide, belongs to the Multiflora division, famous for flowers that are somewhat smaller that most other tuberous begonias (although much larger than those of other types of begonia), but as the name suggest, are produced profusely through the entire summer.

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Begonia tuber

This begonia goes fully dormant in the fall and starts to grow again in the spring. Traditionally the tuber is dug up after the leaves are killed by frost, then kept dry and fairly cool during the winter. They can be stored in vermiculite, peat, sawdust, or newspaper or, if you grow them in pots, just pile the pots one on top of the other in a dark corner. The tubers start to sprout all on their own towards the end of the winter. Repot and start watering them in March or April, about 1-2 months before its time to plant them out.

Multiplication: seed and stem cuttings. You can try dividing larger tubers, but the cut surface often fails to heal properly, which can lead to rot.

C2. Bolivian Begonia (B. boliviensis and its hybrids)

Everything old is new again. My father used to grow this begonia when I was a young child, then it seemed to disappear from the market for decades. It suddenly came into prominence again around 2007 when the cultivar ‘Bonfire’, with orange-red flowers, very much like the old plants I remembered, was introduced. There are now many other varieties in shades of red, orange, yellow, pink and white. The leaves are long and narrow and the flowers have long pointed tepals, giving a tubular flower that hummingbirds love. This cliff-dwelling species has a naturally trailing habit, but there are now more upright cultivars and ones with more open, less tubular flowers.

This begonia goes fully dormant in the fall. Its tuber can be huge! Maintenance and multiplication is exactly like hybrid tuberous begonias and it fact, it is one of the parent species of this group.

C3. Hiemalis Begonia (B. x hiemalis)

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Begonia ‘Dragone White Blushing’

This hybrid species often goes under the names Rieger begonia or Elatior begonia after two hybrid series that were once very popular. Hiemalis means “of winter” and these plants are naturally winter blooming. They come from a cross between summer-flowering tuberous begonias and the rarely grown winter-flowering species, B. socotrana. Despite their theoretical winter bloom, nurseries now offer hiemalis begonias all year long, even as bedding plants for the summer garden. This is done by offering the plants artificially short days. Indeed, once flowering is initiated under short days, the plant will continue to flower for 3 to 4 months even under long days, a technique that makes this plant a very good choice for the summer garden.

The flowers are smaller than those of most tuberous begonias, although larger than other begonia types. They are usually double and come in almost every color except blue. Modern hybrids bloom so profusely that you can scarcely see the foliage! After flowering, the stems start to die back. Ideally, you should cut the plant back at this point and let it rest for 5 or 6 weeks before starting another growing cycle… but hiemalis begonias are notoriously difficult to recuperate at the end of their season, so most gardeners simply buy new plants every year.

Propagation is by stem cuttings… but you may struggle trying to keep the cuttings alive.

C4. Lorraine or Christmas Begonia (B. x cheimantha)

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Begonia x cheimantha

This begonia results from a cross between the winter-flowering B. socotrana and the semi-tuberous B. dregei. The first cultivar was named ‘Gloire de Lorraine’, hence the common name Lorraine begonia. And it is also called Christmas begonia because of its early winter blooming period. Its abundant simple flowers are usually pink or white. Propagation is by stem cuttings… but as with the hiemalis begonia, it is not easy to maintain this plant from one year to the next. This begonia has largely been replaced in garden centers by the hiemalis begonia.

 

C5. Semi-tuberous Begonias

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Begonia dregei

The most common species in this category is B. dregei, a species with a swollen stem base (caudex) and small white flowers, often used in bonsai. With its small leaves and decent branching habit (a bit of pinching will be needed), it looks like a small tree even if its stems are not truly woody. This begonia goes semi-dormant in winter: cut back on watering at that time. Propagation by stem cuttings and seeds.

General Begonia Culture

With such a wide range of different plants, you’d expect to need a lot of varied instructions on how to cultivate them all, but in fact, most begonias do best under pretty similar conditions… as long as you respect their growing season, because some, as mentioned, go dormant and don’t need light or watering for months on end.

In general, begonias prefer partial shade and many will tolerate full shade. Over time, however, many sun-tolerant tuberous and wax begonias have been developed and they do well in full sun, at least in northern regions. Give your begonias rich, loose, well-drained soil, moderate watering (only during the growing season, of course) and decent atmospheric humidity (indoors) and you should have no trouble growing them. They grow as easily in pots (indoors or out) as in the ground. Regular fertilization (during the growing season, of course) will stimulate better bloom, especially for plants grown in pots outdoors and therefore exposed to rain (rain, as wonderful as it may be for plants, has the annoying habit of leaching container soil of all its minerals). In the fall, except in hardiness zones 10-12, almost all begonias will need to move indoors if you want to save them from the cold.

Asexual Propagation

The easiest and quickest method of multiplying begonias is by stem cuttings, a technique that works with almost all varieties. Simply slip a 3 or 4 inch (8-10 cm) section of stem into damp soil, keep the mix moist and the air humid for a few weeks and you’ll soon have a new plant.

Rhizome cuttings are just as easy, the only difference being that you press the rhizome horizontally into the growing mix rather than placing it upright.

You can multiply many begonias (especially rhizomatous begonias, including rex begonias) by leaf cuttings as well.

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Leaf section cuttings.

Take a healthy leaf and insert its petiole into a pot of moist growing mix. No rooting hormone is necessary, but high humidity helps. Thus, it is wise to cover the pot with a transparent plastic bag. Place the cutting in a moderately lit spot and at fairly warm temperatures (21˚C or more)… and wait. A small plant will sprout from the soil after a month or two.

If you need many plants, you can even use leaf sections as cuttings. To do so, cut a leaf into pieces, each with a small bit of midrib or primary vein, and press the sections into moist growing mix. Alternatively, press an entire leaf flat against the soil and cut its veins with a knife: a baby plant will soon poke out of each cut vein.

Sexual Propagation

Begonias are notoriously difficult to grow from seed. The extremely fine seed gives seedlings that are tiny and very fragile at first, and their growth can be slow. It’s often more logical to buy trays of plants in the spring instead of trying to start them yourself. However, if you want to try growing begonias from seeds, here’s how:

You’ll need to so the seeds of begonias you want to plant out very early in the season, in January or February. At that season, however, days are still short, yet begonias need good light to germinate. As a result, germination can be poor or irregular and initial growth almost nil. That’s why it’s best to start begonias under lights, as that gives you full control of day length. Use a timer to set your lamp to 14 hour days: that will ensure good germination and equal growth. Especially don’t expose tuberous begonia seedlings to short days, as they are long day plants and therefore need days longer than 12 hours in order to bloom. In fact, if tuberous begonia seedlings are exposed to short days, that will stimulate tuber formation and put an end to their growth for the season, long before they have time to bloom..

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Pelleted seeds on the left, natural begonia seeds on the right.

Most begonia seeds sold today are pelleted seeds, making them easier to handle. On the other hand, pelleted seeds are also much more expensive.

To sow the seeds, fill a pot or seed tray with moist potting mix, level, and apply the seeds to the surface. Press them lightly into the mix without covering them with soil, because begonia seeds need light to germinate. Spray the container with warm water and put the seed container in a clear plastic bag or inside a mini-greenhouse.

Place the container in about 6 to 12 inches (15 to 30 cm) below a fluorescent lamp. Its gentle heat will help germination, as it should remain above 72˚F (21˚C) day and night. In 7-14 days, sometimes longer, you should see very tiny green leaves appear. At that point, remove the bag or dome to increase air circulation.

Transplant the seedlings in small individual pots when they have two or three leaves. Keep the soil slightly moist (you have to water very gently, preferably from below, as water pouring from the watering can’s spout can easily knock over or bury fragile young seedlings). Also, fertilize occasionally with a soluble fertilizer.

When outdoor temperatures remain above 50˚F (10˚C), acclimate the seedlings to garden conditions and transplant them, preferably into partial shade. Or continue to grow them indoors if you want to use them as houseplants.

Fun Facts About Begonias

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  • The tuberous begonia ‘Kimjongilia’ is one of North Korea’s floral emblems. It blooms annually on the birthday of the country’s late president, Kim Jong-il.
  • Only male flowers of tuberous begonias have double flowers. Begonia experts remove the female flowers to give male flowers more energy to bloom.
  • Begonia flowers are edible and in fact very rich in vitamin C. Their pleasant sweet/tart taste comes from the oxalic acid they contain, the same product that gives spinach and rhubarb their flavor. Since oxalic acid can be toxic if consumed in large quantities, it is best to consume begonia flowers in moderation.
  • In the language of flowers, begonia means “beware”.
  • Begonia seeds are among the smallest in the vegetable kingdom. One gram of begonia seeds can produce up to 100,000 seedlings!

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    Begonia floral carpet in Brussels.

  • Every two years, in August, the Grand Place in Brussels is covered with a huge carpet of tuberous begonia flowers. It takes 120 volunteers about 4 hours and about 600,000 begonia flowers to compose the carpet. The show is spectacular, but don’t miss your flight, as it lasts only three and a half days!