How to Plant and Grow Begonias

Begonias are a garden classic for good reason: This easy-to-grow plant takes root in a variety of conditions and requires little to thrive. Choose any of the many shapes, sizes, and colors, and you’ll be rewarded with stunning flowers and foliage. Some plants showcase single flowers with just one row of petals, while others have double blooms with numerous rows of petals. Keep in mind, begonias—especially the part that’s underground—are toxic to dogs, cats, and horses.

Perhaps the most well-known type, wax begonias are named for the waxy look of their leaves. These reliable plants come in a variety of sizes to fit just about any space, from as small as six inches to nearly three feet tall, and can often handle partial shade or full sun. Their boldly colored flowers, which may be single or double, last throughout the summer. In the wax family alone, you’ll find multiple shades on the white-to-red spectrum.

If you don’t mind a little extra labor, tuberous begonias—which can grow upright or as a trailing plant—promise year-after-year interest. In the fall, simply dig up the tubers, store them indoors over the winter, and then replant them in the spring. The Begonia boliviensis group of tuberous begonias comes in an impressive range of colors, including warm yellows, reds, oranges, whites, and pinks. Rieger begonias are a cross between wax and tuberous varieties, producing large, eye-catching blossoms atop green leaves.

With one central stem, cane begonias are an upright variety, growing up to several feet fall. Expect pretty groupings of dangling flowers with wing-shape leaves, earning this variety the name “angel wing begonias.” These are often grown as houseplants.

Valued for their foliage, rhizomatous begonias have thick stems (called rhizomes) that often grow along the ground. This type tends to form mounds and may feature very large leaves. (Rex begonias, one type of rhizomatous begonia, are grown for their vibrantly colored leaves, which come in an array of hues.) Since this variety likes cooler temperatures, they are often best grown as houseplants. 

Where to Plant Begonias

Begonias are versatile in their requirements: Old-fashioned wax varieties do great in the shade, while several newer wax begonias are perfectly happy in full shade to full sun. Generally, most varieties do well in partial shade, since begonias are naturally a forest understory plant. Those with bronze leaves are typically the most tolerant type for full sun, while green-leaved varieties need a spot with morning sun and afternoon shade to avoid leaf scorch.

Aim to plant begonias quickly after purchasing, ideally in moist, well-drained soil, since persistently wet areas can cause root rot. The optimal soil pH is 5.5 to 6.5. Most varieties won’t tolerate cold temperatures.

Larger wax begonias, some of which can reach nearly three feet tall, are ideal for landscaping, especially planted en masse for a dramatic effect. Smaller begonia varieties, which may be only six inches tall, are well-suited to container gardens, since they won’t crowd out your other plants. Most begonias grow upright; for containers or hanging baskets, look for Begonia boliviensis and angel wing types, which are more cascading.

How and When to Plant Begonias

Most begonias perform best in warm environments, so planting after there’s no longer a chance of spring frost will allow them to thrive. Space begonias about 12 inches apart in flowerbeds (and a bit closer in containers). Be patient after planting, since these beauties take some time to mature. You usually won’t see a burst of growth until after the summer heat kicks in.

Begonia Care Tips

Begonias have a low-maintenance reputation, requiring only the most basic of care: water, well-drained soil, a little sun, and occasional fertilizer. They’re perhaps most finicky when it comes to humidity—some varieties will only thrive with high levels of moisture in the air.

Light

Most begonia varieties like partial shade. Wax begonias can also handle full sun, especially if they have bronze foliage. Direct sunlight can put some varieties, such as cane and tuberous begonias, at risk of leaf scorch.

Soil and Water

Since begonias are prone to root rot in overly moist conditions, seek spots with well-drained soil. Begonia boliviensis varieties in particular like good drainage, as they’re native to cliff walls. If your garden soil is too heavy, add compost or sand to improve drainage.

When it comes to watering, balance is the key to healthy begonias. Most varieties need to be consistently watered but shouldn’t get too wet (too much water can cause root rot and kill them). So don’t be afraid to let your plants dry out a little between waterings, including those in container gardens.

Early morning is the ideal time to give these annuals a drink. Avoid watering during times of day with intense sunlight, as this can lead to leaf scorch. Using a soaker hose and watering at the base of your begonias can reduce the risk of fungal diseases.

Temperature and Humidity

Most varieties grow best in warm temperatures and humid conditions. Wax begonias—the most popular type—are tender in the cold, so it’s essential to plant them after the last frost.

Tuberous begonias should be dug up each year and replanted come spring, since they won’t survive in the cold. Unlike wax begonias, these types won’t thrive in hot, humid conditions, preferring cooler temperatures. Similarly, rhizomatous begonias like milder climates.

Fertilizer

No matter where you plant begonias, it’s smart to give them a regular dose of fertilizer, ideally well-diluted, to fuel the barrage of blooms they’re bound to throw at you. Look for one that’s equal parts nitrogen, phosphorous, and potassium; add it to the soil when you first plant your begonias.

If you want to encourage an abundance of flowers, switch to a fertilizer with more phosphorous than nitrogen once blossoms appear, applying it monthly. However, if pretty foliage is your priority, you can stick with a balanced fertilizer. A controlled-release formula will reduce the odds of burning your begonias. (Rex begonias are particularly prone to this.)

For tuberous begonias, administer a diluted high-nitrogen fertilizer every two weeks, starting at the first flowering and continuing until the end of May. Then begin using a balanced or low-nitrogen formula. Stop fertilizing tuberous types around the end of August; that way, they’ll go dormant and you can dig them up for winter storage.

Pruning

Begonias are self-cleaning, meaning there’s no need to remove (or “deadhead”) old blossoms during the growing season. However, you can periodically prune the plants, especially if they become leggy. Simply pinch the stems back to the first or second healthy bud. Fresh growth will occur at this pinch point, yielding a burst of new flowers and foliage.

Pests and Problems

Pests

Pests aren’t a major problem for begonias. However, they can play host to mealybugs, spider mites, thrips, scale, slugs, and snails.

Fungal Diseases

Keep an eye out for fungal leaf diseases, like powdery mildew, which looks like white dust on the leaves. Avoid overwatering your plants, since overly moist conditions can increase the odds of disease, and grow your begonias in an area with plenty of air circulation.

Begonias may also develop Botrytis blight (gray mold), resulting in a gray, fuzzy layer on the flowers, especially in moist environments. This fungus can spread via splashing, so keep the leaves dry when you water an infected plant.

Pythium root and stem rot, caused by a fungus-like organism, may also affect begonias. In mature plants, the stems nearest the soil may become darker colored and waterlogged, eventually collapsing. This is also linked to overwatering.

If excess moisture causes root rot—a condition begonias are especially prone to—it’s often too late to save the plant.

How to Propagate Begonias

Though there are several varieties of begonias, the propagation process is the same for all of them—and it’s remarkably simple. To propagate from stem cuttings, trim the stems to four inches, then insert the cutting directly into a moist growing medium (like potting soil). This will enable the stems to root properly. Water the cuttings and provide proper light.

Alternatively, you can place cuttings—about 2 to 3 inches of a branch—in water to start the rooting process. Simply pull the leaves off from the bottom half of the cut segment, then place it in water, immersing only the leafless portion. When new roots begin to emerge, you can move the plant to soil.

To propagate begonias from seed, fill pots with seed-starting mix and mist lightly with a spray bottle. Gently place seeds in the pots, loosely covering them with plastic wrap to maintain humidity and warmth. Place the pots in a warm spot out of direct sunlight, while ensuring they receive 14 hours of light each day. Begin the process about 16 weeks before you plan to plant your begonias outside.

Types of Begonias

‘Bellagio Apricot’

‘Bellagio Apricot’ is a double-flowering shade plant with pendulous apricot flowers, perfect for hanging baskets. This variety reaches 14 inches tall and 2 feet wide.

‘Bellagio Blush’

A tuberous variety, ‘Bellagio Blush’ flaunts double white flowers with pale pink edges. It grows up to 14 inches tall and 2 feet wide and prefers full shade.

‘Bellagio Pink’

‘Bellagio Pink’ is a double-flowering shade plant with drooping bright pink flowers, ideal for hanging baskets. It grows up to 14 inches tall and 2 feet wide.

‘Big Red with Green Leaf’

‘Big Red with Green Leaf’ makes a statement with large red-pink flowers and dark foliage. This tough, vigorous plant grows up to 18 inches tall and 12 inches wide.

‘Big Rose with Bronze Leaf’

Another strong and vigorous variety, ‘Big Rose with Bronze Leaf’ will grace your garden with oversized pink flowers and purple-bronze leaves. It grows 18 inches tall and 12 inches wide.

‘Bonfire’

‘Bonfire’ offers glowing orange flowers and narrow, bronzy-green leaves on a plant that’s 20 inches tall and wide. It’s especially well-suited to containers.

‘Cocktail Whiskey’

‘Cocktail Whiskey’ catches the eye with rich bronze-green leaves and crisp white flowers from spring to fall. It grows 7 inches tall and wide.

‘Doublet Rose’

‘Doublet Rose’ features double rose-pink blooms against a backdrop of bronze foliage. It grows 6 inches tall and wide.

‘Doublet White’

Though it stands only 6 inches tall and wide, ‘Doublet White’ is hard to miss with its showy double white blooms. Dark green foliage creates gorgeous contrast.

‘Dragon Wing Red’

‘Dragon Wing Red’ is a vigorous variety that produces an abundance of red flowers. The large blossoms match the plant’s size: It grows up to 18 inches tall and 12 inches wide.

‘Mandalay Pearl’

‘Mandalay Pearl’ produces airy white blossoms all summer long—no matter how hot it gets—and thrives in full sun. This sprawling plant grows 12 inches tall and 30 inches wide.

‘Sprint Scarlet’

‘Spring Scarlet’ offers large red flowers that stand out against medium-green leaves. This compact plant grows 8 inches tall and wide.

‘Super Olympia Coral’

With its large coral-pink flowers and shiny green leaves, ‘Super Olympia Coral’ is a surefire winner in shade or light sun. It grows 8 inches tall and wide.

‘Whopper’

‘Whopper’ is a begonia hybrid series featuring bold colors, sturdy stems, and lush foliage. It tolerates both sun and shade, making it well-suited to almost any landscape. These aptly named plants tower at 24 to 30 inches.

Begonia Companion Plants

Impatiens

What would we do without impatiens? These plants are a reliable addition to shade gardens, promising eye-popping color all season long. Impatiens come in nearly every color (except true blue), and like begonias, they’re well-suited to containers or garden beds.

Lobelia

Few hues can compete with the intense blues of lobelia. Consider planting the mounding type, called edging lobelia, in rows at the front of beds and borders. Or recruit the cascading variety to add a sapphire waterfall to your window boxes or pots. This annual peaks during the cool weather of spring and fall; flowering ceases during the summer, except in milder climates.

Wishbone Flower

Wishbone flower also goes by “clown flower” since its blossoms resemble a cartoonish face. The flowers are shaped like tiny snapdragons, mouths wide open to reveal delicate throats in a contrasting color. Wishbone flower thrives in shade and blooms nonstop until frost.