How and When to Plant Begonias for a Stunning Garden

Table of Contents

1. Introduction
2. Understanding Begonia Types
3. When to Plant Begonias
4. Where to Plant for the Best Results
5. How to Plant Begonia Tubers
6. Caring for Your Begonias
7. Growing Begonias in Containers
8. Overwintering Begonia Tubers
9. Common Simple Wins for Success
10. Conclusion
11. FAQ

Introduction

Shade gardens often feature a lot of greenery, but adding a splash of vibrant color is easier than you might think. Begonias are a favorite for many home gardeners because they turn dim corners into bright, beautiful spaces. These plants offer a massive range of colors and textures, from rose-like blooms to leaves that look like works of art. At Longfield Gardens, we find that begonias are some of the most rewarding flowers to grow because they bloom continuously from early summer right through the first frost.

This guide is designed for any gardener who wants to master the art of growing these tropical beauties. For a broader primer, read All About Begonias. We will cover exactly when to get your tubers in the ground and how to plant them for the best results. Whether you are planting in containers on a porch or directly into your garden beds, these steps will help you succeed. By the end of this article, you will feel confident in your ability to choose, plant, and care for begonias.

Getting the timing and technique right is the most important part of the process. Begonias have a few specific needs, but once those are met, they are very low-maintenance plants. Our goal is to help you create a lush, colorful display that lasts all season long. With a little bit of planning, you can enjoy these spectacular flowers year after year.

Understanding Begonia Types

Before you decide when and how to plant, it is helpful to know which type of begonia you are working with. While there are thousands of varieties, most home gardeners choose from a few main categories. Each one has a slightly different growth habit and use in the landscape.

Tuberous Begonias

Tuberous begonias are the stars of the shade garden. They grow from a thick, potato-like root called a tuber. These are famous for their large, dramatic flowers that can look like roses, camellias, or carnations, and Begonia Upright Double Roseform Pink is a good example. You can find upright varieties that stand about 12 inches tall or trailing varieties that spill beautifully over the sides of hanging baskets. Most of our advice in this guide focuses on these because they are started from dormant tubers in the spring.

Wax Begonias

Wax begonias are smaller, fibrous-rooted plants. They have glossy, succulent-like leaves that come in green or bronze. These are often used as bedding plants for borders or mass plantings. They are very tough and can handle a bit more sun than their tuberous cousins. Because they are usually sold as started plants in "six-packs," the planting process is slightly different than starting with tubers. For more on the different kinds, see Types of Begonias.

Rex and Rhizomatous Begonias

These types are primarily grown for their incredible foliage. Their leaves feature swirls of silver, purple, pink, and deep green. While they do produce small flowers, the leaves are the main attraction. Many gardeners grow these as houseplants or use them as "filler" plants in shaded containers to add texture and interesting patterns.

Key Takeaway: Choose tuberous begonias for big, showy flowers in pots or beds. Use wax begonias for low-growing borders and Rex begonias for stunning leaf patterns.

When to Plant Begonias

Timing is everything when it comes to begonias. Because they are tropical plants, they have no tolerance for frost or cold soil. If you plant them too early, the tubers may rot in cold, damp ground. If you wait too late, you miss out on weeks of beautiful blooms.

Following the Frost Schedule

The most important rule is to wait until all danger of frost has passed. Begonias thrive in warm weather. We recommend waiting until the outdoor nighttime temperatures are consistently above 60°F. In most parts of the United States, this happens in late May or early June.

If you are unsure of your local frost date, you can check with a local university extension office or use a digital hardiness zone map. At Longfield Gardens, we time our shipping based on your USDA hardiness zone; see our Shipping Information. This ensures your tubers arrive about two weeks before the ideal planting time for your specific area.

Starting Begonias Indoors

If you live in a northern climate with a short growing season, you can get a head start by planting your tubers indoors. This is one of the best ways to ensure you have flowers by early summer. You can start this process about 8 to 12 weeks before your last expected frost date.

Starting indoors gives the tuber time to wake up, grow roots, and send up its first leaves in a controlled, warm environment. By the time the weather is warm enough to move them outside, you will have a sturdy plant ready to bloom. For more detail, see Tips for Growing Tuberous Begonias. This extra time is especially helpful for trailing varieties used in hanging baskets.

Soil Temperature Matters

Air temperature is a good guide, but soil temperature is even more accurate. Begonia tubers will sit dormant until the soil reaches at least 60°F. If the soil is cold and wet, the tuber is at risk of rotting before it ever starts to grow. If you are planting directly into the ground, wait for a stretch of warm, sunny days to ensure the earth has warmed up.

Where to Plant for the Best Results

Choosing the right spot is the first step toward a healthy plant. Begonias are famous for loving the shade, but "shade" can mean many things. Finding the right balance of light and protection will keep your plants happy.

Light Requirements

Most begonias prefer filtered light or partial shade. Think of the light found under a tall tree or on a porch that gets morning sun but is shaded during the heat of the afternoon.

• Morning Sun: This is the gentlest light and is usually very safe for begonias.
• Dappled Shade: This is ideal. It provides enough energy for flowering without scorching the leaves.
• Deep Shade: Begonias will grow here, but they may produce fewer flowers and become "leggy" as they stretch for light.
• Direct Afternoon Sun: This is often too intense. It can cause the leaves to turn brown or develop "burn" spots.

Soil and Drainage

Begonias need soil that stays moist but never stays soggy. Good drainage is non-negotiable. If you are planting in the ground, look for a spot where water doesn't pool after a rainstorm. If your soil is heavy clay, you can improve it by mixing in some compost or peat moss to lighten the texture.

For containers, always use a high-quality potting mix. Avoid using "garden soil" or "topsoil" in pots, as these are too heavy and will pack down, preventing air from reaching the roots. Make sure every pot has at least one drainage hole.

Protection from Wind

Tuberous begonias have thick, succulent stems that can be quite brittle. Heavy winds or intense rain can snap the stems of upright varieties. If you live in a windy area, try to plant your begonias in a sheltered spot, such as near a fence, a wall, or under a porch roof.

What to do next:

• Identify the shady spots in your yard that get 4–6 hours of gentle light.
• Check your pots for drainage holes.
• Prepare your soil with compost if it feels heavy or sticky.

How to Plant Begonia Tubers

Once the weather is right and you have your spot picked out, it is time to plant. Planting a tuber is a simple process, but there are a few details that make a big difference in how well the plant grows.

Step 1: Identify the "Up" Side

Begonia tubers have a distinct shape. One side is usually rounded, and the other side has a hollow or indented "bowl" shape. The hollow side is the top. This is where the new sprouts will emerge. The rounded side is the bottom, where the roots will grow.

If you look closely at the hollow side, you might see tiny pink or white buds starting to swell. These are called "eyes," similar to the eyes on a potato. If you truly cannot tell which side is which, you can plant the tuber on its side, and the plant will figure out which way to grow.

Step 2: Planting Depth

Begonias do not like to be buried deep in the earth. In fact, planting them too deep is a common reason they fail to sprout.

• In Pots: Place the tuber on top of the soil and press it down so the top is just barely covered or even level with the soil surface.
• In the Garden: Dig a shallow hole and cover the tuber with no more than 1/2 inch to 1 inch of soil.

Keeping them near the surface allows the sun to warm the tuber, which encourages faster sprouting.

Step 3: Spacing

Give your begonias room to breathe. Good air circulation helps prevent diseases like powdery mildew.

• For upright varieties in the garden, space them 8 to 12 inches apart.
• In a 12-inch hanging basket, you can plant two or three trailing tubers for a full, lush look, such as Begonia Hanging Pink Balcony.
• In window boxes, space them about 6 to 8 inches apart.

Step 4: Initial Watering

After planting, water the soil lightly to help settle it around the tuber. Be very careful not to overwater at this stage. Since the tuber doesn't have roots yet, it cannot take up much moisture. The soil should feel like a wrung-out sponge—damp but not dripping. Too much water at the start can cause the tuber to rot before it wakes up.

Caring for Your Begonias

After your begonias have sprouted and developed a few leaves, they enter a period of rapid growth. This is when they need consistent care to produce those famous flowers.

Watering Correctly

Begonias prefer consistent moisture. The goal is to keep the soil evenly damp. In the heat of summer, containers may need water every day, while garden beds might only need it once or twice a week.

The best way to check is with your finger. Stick your finger an inch into the soil. If it feels dry, it is time to water. If it still feels moist, wait another day. Always try to water at the base of the plant rather than over the leaves. Wet leaves in the shade can lead to fungal issues.

Feeding Your Plants

Begonias are "heavy feeders," meaning they need a lot of nutrients to keep blooming all summer. We recommend using a balanced, water-soluble fertilizer every two weeks. Look for a fertilizer labeled for flowering plants.

If you are growing in containers, nutrients wash out of the soil every time you water. Frequent, light feeding is better than one heavy dose. Following the instructions on the fertilizer label is the best way to ensure your plants get exactly what they need.

Deadheading and Grooming

Begonias are generally "self-cleaning," which means the old flowers will eventually fall off on their own. However, removing spent blooms (deadheading) keeps the plant looking tidy and encourages it to put more energy into new flowers.

You should also remove any yellowing or damaged leaves. This keeps the plant healthy and prevents pests from hiding in the debris. If an upright begonia becomes too tall or "top-heavy," you can use a small bamboo stake to give it some extra support.

Growing Begonias in Containers

Many people find that begonias perform best in pots. This is because it is easier to control the soil quality, drainage, and light. For compact displays, Non Stop Begonias are especially handy in window boxes and planters.

Choosing the Right Pot

Plastic, ceramic, or resin pots all work well for begonias. If you use terracotta, keep in mind that it breathes and dries out much faster than plastic. This can be a benefit if you tend to overwater, but you will need to check the moisture level more often.

Trailing vs. Upright in Containers

• Trailing (Pendula) Begonias: These are the best choice for Hanging Begonias or the edges of large planters. They will grow out and then cascade down, creating a waterfall of color.
• Upright Begonias: These are perfect for Upright Double Begonias. They provide height and a sturdy structure.

Mixing with Other Plants

Begonias play well with others. You can create a stunning shade container by mixing tuberous begonias with foliage plants like coleus, ferns, or caladiums. Just make sure all the plants in the pot have the same light and water requirements.

Key Takeaway: For the best container display, use a high-quality potting mix, ensure good drainage, and fertilize every two weeks to keep the blooms coming.

Overwintering Begonia Tubers

In most of the United States, begonias are treated as annuals because they cannot survive the winter. However, you can save your tubers and replant them next year. This is a great way to save money and keep your favorite varieties going.

When to Bring Them In

Wait for the first light frost in autumn. The frost will turn the leaves and stems black or yellow, which signals the plant to go dormant. This is the natural time to dig them up.

The Drying Process

Carefully dig up the tubers, being careful not to nick or bruise them. Cut the stems back to about an inch above the tuber. Lay the tubers out in a dry, cool, shady spot (like a garage or basement) for a few days. This allows the outer skin to "cure" or toughen up. Once they are dry, you can gently brush off the excess soil.

Storage Conditions

Store your tubers in a way that allows them to breathe. A cardboard box or a paper bag filled with peat moss, vermiculite, or shredded paper works perfectly. Keep the box in a cool, dark place where the temperature stays between 40°F and 50°F. Do not let them freeze.

In the spring, about 8 weeks before the last frost, you can take them out of storage, check for any soft spots, and start the planting process all over again.

Common Simple Wins for Success

Gardening is most enjoyable when you focus on the simple things that produce big results. With begonias, success usually comes down to three things:

1. Don't Rush the Heat: Waiting for warm soil is the single best thing you can do for a begonia.
2. Watch the Water: It is better to let the soil dry out slightly than to keep it soaking wet.
3. Feed the Flowers: Regular fertilizer is the secret to those huge, rose-like blooms you see in professional gardens.

If your plant isn't blooming as much as you'd like, try moving it to a spot with just a little bit more light. If the leaves are turning brown at the edges, it might be getting too much sun or not enough water. Small adjustments like these are part of the fun of gardening.

Conclusion

Begonias are a fantastic choice for adding long-lasting color and elegance to the shaded parts of your yard. By understanding how and when to plant them, you can enjoy a professional-looking garden with very little stress. At Longfield Gardens, we take pride in providing high-quality tubers that are ready to thrive in your home landscape. Remember that gardening is a journey, and every season is a chance to learn something new about your plants and your environment.

• Wait for warm weather and soil temperatures above 60°F before planting outside.
• Plant tubers hollow-side up and just below the soil surface.
• Provide partial shade and consistent moisture for the best blooms.
• Fertilize every two weeks during the growing season.

Getting the basics right—like timing, depth, and drainage—takes the guesswork out of gardening. Once your begonias start blooming, you will see why they have been a garden favorite for generations.

We are here to support you with quality plants and practical advice. If you ever have a question about your order or need a bit of guidance on a specific variety, please Contact Us. Our team is ready to help. Happy planting!

FAQ

Which side of the begonia tuber should face up?

The side with the hollow, bowl-like indentation should face up. This is where the stems and leaves will grow. The smooth, rounded side should face down into the soil where the roots will develop. If you see tiny pink buds or "eyes," those should always point upward.

Can begonias grow in full sun?

Most begonias, especially tuberous varieties, prefer partial shade or filtered light. While wax begonias can handle more sun, especially in cooler northern climates, tuberous begonias will likely experience leaf scorch if left in the intense afternoon sun. Providing them with morning sun and afternoon shade is usually the safest approach.

How long does it take for begonia tubers to sprout?

Begonia tubers are notoriously slow to wake up. It usually takes between 2 to 4 weeks to see the first green sprouts emerge from the soil. If your soil is on the cooler side, it may take even longer. Be patient and avoid overwatering during this period, as the tuber is still dormant or just starting to grow roots.

Do I need to dig up my begonias every year?

If you live in USDA zones 8 or warmer, you may be able to leave your begonias in the ground year-round. However, in zones 3 through 7, the tubers will freeze and die if left outside over the winter. In these colder regions, you must dig them up after the first frost and store them in a cool, dry place to save them for the following year.