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Begonias | Ultimate Growing and Care Guide

In lush and leafy shade gardens, there is one flower who reigns supreme, the begonias. Shade gardens often rely on different shapes and textures of foliage for interest, not many flowers bloom in shady areas.

However, begonias have stunning blooms in a variety of colours, bringing color and beauty to the darker corners of gardens. As a bonus, they are surprisingly low maintenance and easy to grow as long as they are in the right conditions.

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Begonias Ultimate Growing and Care Guide

Get to Know Begonias 

Begonias were discovered in the late 17th century by Franciscan monk Charles Plumier, who made the discovery of the fibrous begonias in the rainforests of Brazil

Begonias were discovered in the late 17th century by Franciscan monk Charles Plumier, who made the discovery of the fibrous begonias in the rainforests of Brazil.

There are now over a thousand species of begonias, prized for their beautiful flowers and foliage. There are four main types of begonias (more info on each below), so there is a type for every gardener. 

Houseplants, Garden plants, and even a perennial (certain type, in certain zones). This plant are mostly known as shade loving flowers, brightening up shady garden corners with their big bold blooms. 

They are so versatile and beautiful, they belong in any and every home and garden.

Types of Begonias

Begonias are categorized into four main types based on their roots, tuberous, fibrous, rhizomatous, and hardy. Let’s look into each category.

Tuberous Begonia 

Tuberous Begonia is what immediately comes to mind when picturing a begonia

This variety is what immediately comes to mind when picturing a begonia. Large, bold, striking flowers dangling heavy from tuberous stems.

This is the variety used in garden beds to add a shock of color to shady areas, and in containers to add a non-stop blast of neon color. These are a few popular varieties of tuberous begonias:

  • Nonstop Begonia (Begonia x tuberhybrida) - the Nonstop series of tuberous begonias is spectacular. Growing 8-10 inches in height they produce large, often double, flowering plants. They come in a variety of colors.

    Nonstop fire begonias have yellow centres and then the tips of the flowers are bright red. Nonstop red begonias are huge ruffled blooms of a rich red color, they look like roses.
  • On Top Begonia - the On Top series of tuberous begonias are another large, double flowering variety. They grow 10-12 inches in height and flower all season long even in periods of above average heat.

    On Top Fandango is a gorgeous variety featuring white centres with frilly pink edges. 
  • Amstel Begonia - Amstel begonias are actually a hybrid of tuberous and fibrous begonias (more on fibrous below), they feature flowers that sit upright on the plant (as opposed to dangling down like the Nonstop and On top varieties).

    The flowers hold on for a long time through the season and require little deadheading (the process of removing dead flowers to encourage new flowers to grow).

    They come in a variety of colors such as red, white, yellow, and pink.

Fibrous Begonia (Wax Begonia)

Fibrous begonias are a low growing begonia with smaller flowers than the tuberous variety

Fibrous (Wax) begonias are a low growing begonia with smaller flowers than the tuberous variety. They look great when planted in masses or as borders, creating more impact when there are many of them planted together. These are a few popular varieties of fibrous or wax begonias:

  • Olympia Begonia - This variety is a nice uniform variety that comes in red, white, and pink shades. They grow 6-8 inches in height and are very uniform, making them ideal for borders and mass plantings.
  • Cocktail Begonia - Cocktail variety grows 8-12 inches, also with flowers in the red, white, and pink shades. However, Cocktail begonias feature beautiful scarlet bronze leaves, making them unique and striking (especially when paired with something with chartreuse foliage such as a potato vine).
  • Dragon Wing Begonia - This variety is usually put into hanging baskets and containers, it has pointed waxy foliage and spikes of flowers dripping down.

Rhizomatous Begonia 

Rex Begonia is probably the most well known and popular of the rhizomatous begonias

Rhizomatous are the foliage begonias, the ones that are kept mostly as houseplants because of their striking foliage colors and patterns. These are a couple popular varieties of rhizomatous begonias:

  • Rex Begonia - Probably the most well known and popular of the rhizomatous begonias. They make great houseplants, with their striking foliage.

    Varieties of Rex range from purples, greens, and whites, with a variety of patterns, swirls, and stripes. Rex begonias are works of art.
  • Eyelash Begonia - This are creeping variety with pretty heart shaped leaves adorned with darker colored ‘eyelashes’ along the perimeter of the leaf.

Hardy Begonia 

Hardy begonia is probably the least well known of the begonia varieties

The hardy begonia (Begonia grandis) is probably the least well known of the begonia varieties. It can be grown in USDA zones 6-9. They grow up to 3 feet in height, and add an extra touch of whimsy to the shade garden. These are a couple of popular varieties of hardy begonias:

  • Heron’s Pirouette - This variety will grow 2 feet in height with lovely heart shaped begonia leaves and then large sprays of light pink flowers.
  • Begonia grandis 'Sapporo' - this variety will grow 18-24 inches tall and has lighter green begonia leaves with reddish stems and sprays of pink flowers.

How to Grow Begonias 

Begonias can be purchased from nurseries and garden centres as starter plants and then planted into pots in the home, or into the garden.

When transplanting the plant from the nursery pot make sure to break up the roots a bit before planting begonias.

How to Grow Begonias

Planting Begonias from Seed

Begonias can also be planted from seed. It is best to purchase the seeds to make sure they are viable, as many grown nowadays are hybrids, these varieties will not make seed that will grow into the same plant. 

Start begonia seeds early, 10-12 weeks before the last frost. Begonia seeds are tiny, scatter them lightly onto damp seed starting mix and spray lightly with water.

Unlike a lot of plants, begonia seeds actually require light in order to germinate, keep a dome lid on them to keep the moisture in, but do not place them in a dark warm place instead place them in a bright sunny area until they start to sprout (anywhere from 2-3 weeks), then remove the dome lid.

Plastic berry containers or take out containers are great to use as seed starters as they already come with their own lid. Seed starting trays can also be purchased.

Either way, make sure there are holes in the bottom of the container so that excess water can drain through. Next, keep the seedlings in bright (south exposure), or 4-6” from a grow light.

After they start sprouting, they may need to be thinned out so they are growing 4-6” apart (or for cell packs, 1 plant per cell). Once they are grown and ready to be planted, it is important to slowly introduce them to an outdoor environment.

This is called ‘hardening off’, start by bringing the seedlings out to a shady area for a couple hours and then bringing them in, and then slowly leave them outside longer each day until they full acclimatized, and ready to be planted into the garden (noting that these are shade plants, so don’t introduce them into long periods of full afternoon sun).

Propagating Begonia by Cuttings

Propagating Begonia by Cuttings

Begonias can also be propagated by cuttings.  Make sure when taking a cutting to cut 4” of the plant and include a point where a leaf would sprout from (this is a node), place in water until it sprouts roots and then plant in moist soil and place a bag or dome over it for a week to hold in moisture.

The cutting can also be dipped in rooting hormone and planted directly into moist soil with a bag or dome over it for the first week. (Here is our review on the best rooting hormones you can get online.)

The leaves might be really droopy and sad looking at first, but they will perk up once they start rooting and the roots take hold.

Planting Begonias from Tubers

Tuberous begonias can also be planted from tubers (as their name suggests). Tubers can be obtained from a garden center and should be started indoors 4-6 week before the final frost date.

Plant tubers in potting mix with their hollow side up and cover lightly with soil. Moisten the soil and keep it moist and allow the tubers to sprout.

Once the begonias have grown, they can be pruned into smaller single stems for more compact, densely flowering plants, or left alone, for large, more sprawling begonias. Use the hardening off process mentioned above once they are ready to go outside.

Caring for Begonias

Caring for Begonias

Sun Requirements

Begonias are the king of the shade. Outdoors, they like shady areas of the gardens. Shade planters with a Northern or Eastern exposure. Varieties with darker leaves, such as ‘Cocktail’ will take more sun than other varieties.

While they are shade plants, they do not bloom well in deep dark shady parts of the garden, they will need some early morning, or late afternoon sun to really thrive. Begonias grown for foliage can handle more shady conditions.

Houseplant varieties of begonias like bright indirect sunlight. Not up against a southern exposure, nor in a dark corner of the home. Think away from a Southern window, or up against a Northern or Eastern exposure.

Soil Requirements

Light, fluffy, beautiful potting soil with lots of organic matter is best for begonias. Heavy clay soil does not provide adequate drainage and while begonias may survive in it, they will not thrive.

How to Water Begonias

Begonias are actually a surprisingly drought tolerant plant, especially the tuberous variety. They will turn crispy if they are not watered enough, but a day or two left dry and begonias are usually ok.

Outdoors, on hot days they will need to be watered daily, especially if they are in containers. If they are in the garden, it could be daily, weekly, depending on the weather and soil.

Check for crispy edges and drooping leaves as signs they need extra water.  Do not over water begonias, they will rot. Indoors, begonias need to dry out, but not completely between watering, check with a finger to see if the soil is moist or dry. 

Weekly watering is usually sufficient. Again, do not over water, they will rot. A moisture meter is a handy tool to get a better grasp on watering. 

Fertilizing Begonias

For begonias that are grown for their flowers and all purpose 20-20-20 fertilizer is great, or a fertilizer that promotes blooms. Fertilize once a week in the growing season.

For indoor, foliage begonias (Rex etc) fertilize with a balanced indoor fertilizer once every 2-3 weeks during their active growing season. The hardy perennial begonia variety doesn't require any special fertilizer, instead consider adding worm casting, or compost to amend the soil.

(Do you want to make composting easier? Get the best compost tumbler for 2022 here.)

Companion Planting Your Begonias

Begonias are shade loving plants, however not full deep shade

Now for the fun part! Designing garden beds, containers, and homes with begonias. They are such a versatile plant, and there are endless combinations and ideas of things to do with them. Here are a few ideas:

Tuberous varieties look gorgeous in both the garden and in containers. In shady garden beds, where things are mainly green, the big bold flowers of tuberous begonias add a sharp bolt of color. 

Consider adding them amongst hostas to break up the green. Tuberous begonias are a star in containers, consider planting a palm or an elephant ear in the middle with tuberous begonias all around and ivy trailing out the sides.

Fibrous, or wax begonias (such as Olympic or Cocktail) make great borders and mass plantings. With their uniform growth and flowers, they turn into a homogeneous mass of flowers and foliage that the eye can glide pleasingly over in the garden.

Stick to a single colour, for a more formal look, or go with a mix of a single variety (e.g. Olympic mix) for a more casual, cottage feel.

Rhizomatous varieties are mostly considered houseplants. Choose a beautiful pot with drainage to display the begonia’s stunning foliage. Pick a container that is only slightly larger than the begonia itself. 

Terracotta pots look great, or a pot with a colour that compliments the begonias foliage. The foliage can be so ornate, simple solid-colored pots look great.

Hardy types should be planted in the shady areas of the garden, perhaps among hostas and ferns. It’s a mid-sized perennial, so it can grow behind a lower, creeping perennial such as lily of the valley, or sweet woodruff. It provides a beautiful pop of flowers to a mostly foliage focused shade garden.

Common Begonia Pests and Diseases

If kept in their ideal growing conditions, begonias are rarely a problem in the home and garden. Before discussing possible pests and diseases, it is important to rule out one of the most common problems with any plant, watering.

Rotting Stems/Yellow Mushy Leaves 

If your plant have rotting stems, and/or yellow mushy leaves, it is quite possible the begonia is being over watered. Cut back the watering, check the soil to see if it is dried out before watering. 

If they are planted in the ground, they may have to be transplanted if they are in too boggy of an area. Alternately if the edges are crispy and the leaves are dying it could be not enough water. 

If the begonia is in a container try pouring water through the pot and letting it flow through, or submerging the bottom of the pot (make sure your pot has a drainage hole in the bottom) and let the water soak up and then pour off excess. 

Ok, so it’s not a watering issue, what else could be attacking your plant? As far as pests go, this plant are susceptible to the usual culprits, mealy bugs, spider mites, and slugs/snails. 

How to Propagate Begonias

Mealy Bugs and Spider Mites

For mealy bugs and spider mites a spray with an insecticidal soap and going over every leaf with a cotton swap and a diluted hydrogen peroxide mixture will help rid them of these pests.

If bringing begonias indoors to over winter them, assume they will have spider mites and spray them preventatively with an insecticidal soap and keep them quarantined from other houseplants for a couple of weeks.

Another method that will hold off spider mites (if on outdoor annuals that won’t be around forever anyways) is a good spray with the garden hose.

Remember healthy plants are not as susceptible to pests, so make sure to have the begonias growing in their ideal growing conditions.

Snails and Slugs

For snails and slugs, watering conditions are usually a problem, so cut back on watering. If it’s just a rainy wet year in the garden, apply a slug bait to the garden weekly as needed.

Shallow containers of beer placed in the garden will lure the slugs and snails for easier disposal. Or for the garden keener, never underestimate the power of waking up early and hand picking them off the plants (yuck! But it works…). 

Powdery Mildew

As for diseases, the most common one to affect your plant will be powdery mildew. To prevent powdery mildew, give begonias space so they have adequate airflow and don’t over water them. 

Once it appears, spray the foliage with a fungicide. There are many home remedies for powdery mildew, but use these with caution, just because they use common ingredients found around the home (dish soap, vinegar, baking soda etc), doesn’t mean they are not chemicals that will harm the balance in a garden.

Begonia FAQs

How to Care for Begonias

Do begonias like shade or sun?

Begonias are shade loving plants, however not full deep shade. Early morning, or late afternoon sun suits them best. Do not plant them in full hot afternoon sun.

Do begonias do well in pots? 

Yes! They can be grown in containers outdoors as part of an arrangement, or they can be grown in pots by themselves as houseplants.

Do begonias grow back year after year?

The hardy varieties of begonia are perennial (zones 6-9) and will grow back yearly. The tuberous, fibrous, and rhizomatous varieties will die after the first frost, however they can be overwintered indoors and brought back outside.

Why are the leaves on my begonia turning white?

This is most likely powdery mildew. Shade loving plants are more susceptible to powdery mildew. Spray the plant with an organic fungicide.

Do this in the morning or evening, not in the heat of the day. To prevent it in the future, give begonias space for airflow and do not over water them.

Can begonias survive outside?

Yes! However, they are very sensitive to cold and cannot take a lick of frost. Check the frost dates in your area to determine when it is safe to bring or plant outside.

Are begonias good in hanging baskets

Absolutely! Try tuberous begonias in a large moss planter, their big bold flowers will spill over the edges. Fibrous types such as a dragon wing begonia also do wonderful in hanging baskets.

Time to Introduce Begonias in Your Home

Begonias are a home and garden staple. Try all four varieties, they don’t disappoint! From a beautiful flowering annual, to a striking foliage plant, and even a hardy perennial, there is a begonia for every plant enthusiast. 

About the Author Mabel Vasquez

Mabel has enjoyed a long career as a horticulturist, working in nurseries and greenhouses for many years. Although she loves all plants, Mabel has developed a particular passion over the years for herb gardens and indoor plants. Mabel has since retired from her horticulture career and loves sharing her many years of experience with our audience here at Sumo Gardener.

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