Best Timing and Tips for When to Grow Begonias

Table of Contents

1. Introduction
2. Understanding Begonia Types and Their Timelines
3. When to Start Begonias Indoors
4. Moving Begonias Outdoors: The Temperature Rule
5. Understanding USDA Hardiness Zones and Shipping
6. When Do Begonias Bloom?
7. When to Water and Fertilize
8. When to Move or Store Begonias for Winter
9. Troubleshooting Common Timing Issues
10. Selecting the Right Varieties for Your Timeline
11. Conclusion
12. FAQ

Introduction

Shady corners of the garden often feel like a challenge, but they are actually the perfect stage for one of the most rewarding flowers you can plant. Begonias offer a spectacular display of color and texture that lasts from the heat of summer all the way through the first touch of frost. Whether you are looking for the massive, rose-like blooms of tuberous varieties or the dainty, constant flowering of wax begonias, success starts with understanding their unique rhythm. (longfield-gardens.com)

At Longfield Gardens, we want to make it easy for you to enjoy these tropical beauties in your own backyard. Many gardeners feel a bit of pressure when it comes to timing, but begonias are actually quite flexible once you know their basic needs. This guide is designed for any gardener who wants to master the timeline of these stunning plants, from the first indoor sprout to the final autumn harvest.

We will cover exactly when to start your begonias indoors, the right time to move them to the garden, and how to manage their growth throughout the year. By following a few simple steps, you can ensure your garden stays vibrant even in the deepest shade. Getting the timing right is the most effective way to guarantee a season full of effortless, brilliant color. (longfield-gardens.com)

Understanding Begonia Types and Their Timelines

Before we dive into the specific months on the calendar, it is helpful to identify which begonias you are growing. While there are thousands of species, most home gardeners focus on three main categories. Each has a slightly different timeline, but they all share a love for warmth and a hatred for frost. (longfield-gardens.com)

Tuberous Begonias

These are the stars of the shade garden. They grow from thick, potato-like tubers and produce some of the largest and most intricate flowers in the begonia family. Some varieties grow upright, making them perfect for garden beds and window boxes, while others have a cascading habit that looks beautiful in hanging baskets. Because they grow from a stored energy source (the tuber), they have a specific wake-up and sleep cycle that we can use to our advantage. (longfield-gardens.com)

Wax Begonias

Often used as bedding plants, wax begonias are fibrous-rooted. They are generally treated as annuals in most of the United States. They are tough, sun-tolerant compared to other types, and bloom incessantly. Their timing is simpler because they are usually purchased as established nursery plants in the spring, though you can grow them from seed if you start very early in the winter. (longfield-gardens.com)

Rex and Rhizomatous Begonias

These varieties are primarily grown for their incredible foliage. While they do produce flowers, the main event is the swirling patterns and metallic colors of their leaves. These are often grown as houseplants year-round, but many gardeners move them outdoors for the summer. Their "when" is more about the temperature of the air than a specific blooming season. (longfield-gardens.com)

Key Takeaway: Identifying your begonia type is the first step. Tuberous begonias require the most planning regarding timing because they have a distinct dormancy period. (longfield-gardens.com)

When to Start Begonias Indoors

One of the best ways to get a head start on the season is to begin your tuberous begonias indoors. Since these plants are native to tropical regions, they need a long growing season to reach their full potential. If you wait until it is warm enough to plant them directly in the ground, you might not see blooms until late summer. (longfield-gardens.com)

The 8 to 12 Week Rule

For the most satisfying results, we recommend starting begonia tubers indoors about 8 to 12 weeks before the average last frost date in your area. For many gardeners in the northern half of the country, this means starting them in February or March. This window gives the tuber enough time to develop a strong root system and several inches of top growth before it ever sees the outdoors. (longfield-gardens.com)

Why Start Early?

Starting early isn't just about impatience; it’s about plant health. A begonia that has already "woken up" in the safety of your home will be much more resilient when it finally moves to the garden. By the time the weather is truly warm, an early-started begonia can be nearly ready to bloom, giving you a much longer window of color. (longfield-gardens.com)

Signs of Life

When you receive your tubers from us, they may already show tiny pink or white buds in the "bowl" or indented side of the tuber. This is a great sign! It means the plant is ready to grow. If they look dormant, don't worry—warmth and a little moisture will wake them up within a few weeks.

What to Do Next: Starting Indoors

• Select a shallow tray or individual small pots with excellent drainage.
• Use a high-quality, pre-moistened potting mix.
• Place the tuber with the hollow (indented) side facing up.
• Cover with just a half-inch to an inch of soil.
• Keep the pots in a warm spot (around 70°F) with bright, indirect light.

Moving Begonias Outdoors: The Temperature Rule

The most common mistake gardeners make with begonias is moving them outside too early. Because begonias are tropical plants, they have no defense against the cold. Even a light frost can turn a healthy plant into mush overnight. More importantly, begonias won't really grow if the soil is chilly. (longfield-gardens.com)

Monitoring Soil Temperature

Instead of just looking at the calendar, look at the thermometer. Begonias thrive when the soil temperature reaches at least 60°F. If the ground still feels cold to the touch, it is better to keep your begonias in their pots on a porch or inside a little longer. (longfield-gardens.com)

Nighttime Air Temperatures

The air temperature is just as critical as the soil. We recommend waiting until nighttime temperatures are consistently above 50°F—and ideally closer to 60°F—before leaving begonias outside overnight. If you have a sudden cold snap in late May or early June, be prepared to bring your containers back inside or cover your garden beds with a light fabric.

The Hardening Off Process

When it is finally time to move your indoor-started begonias out, do it gradually. This is called "hardening off." Spend about 7 to 10 days transitioning them.

1. Days 1-3: Place them in a fully shaded, protected spot for a few hours in the afternoon.
2. Days 4-6: Increase their time outside and allow them to experience very dappled morning light.
3. Days 7-10: Leave them out all day and eventually overnight, provided the weather stays warm.

Key Takeaway: Patience is a virtue with begonias. Waiting for warm soil and steady nighttime temperatures ensures your plants won't be stunted by a late-spring chill. (longfield-gardens.com)

Understanding USDA Hardiness Zones and Shipping

At Longfield Gardens, we time our shipping based on your USDA hardiness zone. This helps ensure that your tubers arrive at the right time for planting in your specific climate. (longfield-gardens.com)

Warm Climates (Zones 8-11)

In these regions, begonias can often be grown as perennials. If you live in a place where the ground does not freeze, you may be able to leave your tubers in the soil year-round. However, even in warm zones, begonias still appreciate a rest period in the winter. If your winters are very wet, it is often better to lift the tubers anyway to prevent them from rotting in soggy soil. (longfield-gardens.com)

Cold Climates (Zones 3-7)

In the vast majority of the U.S., begonias are treated as annuals or "tender perennials." This means they will not survive the winter outdoors. Gardeners in these zones are the ones who benefit most from starting tubers indoors in late winter to maximize the summer bloom time. (longfield-gardens.com)

Shipping Expectations

We typically ship orders so they arrive about two weeks before the ideal planting time for your zone. This gives you a little window to get your pots and soil ready. Remember that nature is unpredictable; if your shipment arrives but your local weather is still showing signs of a deep freeze, keep your tubers in a cool, dry place until the extreme weather passes. (longfield-gardens.com)

When Do Begonias Bloom?

Once your begonias are established in the garden, the real show begins. One of the best things about begonias is their "non-stop" nature. Unlike spring bulbs that bloom and then disappear, or perennials that have a specific two-week window of glory, begonias are marathon runners. (longfield-gardens.com)

Summer Peak

Most begonias will begin their main flowering show in July. Once they start, they generally do not stop until the weather turns cold in the fall. If you started your tubers indoors in February or March, you might even see your first flowers as early as June. (longfield-gardens.com)

The Fall Finale

Begonias often look their best in late August and September. As the days get slightly shorter and the extreme heat of mid-summer breaks, begonias frequently put on a massive growth spurt. This late-season surge is a wonderful way to keep your garden looking fresh when other summer flowers might be starting to fade. (longfield-gardens.com)

Factors That Affect Timing

While begonias are consistent, a few things can shift their blooming schedule:

• Light Levels: Begonias in deep shade will bloom a bit later and less profusely than those in "bright shade" or dappled sunlight.
• Fertilizer: Regular feeding helps the plant have the energy to produce flowers continuously.
• Heat Stress: During periods of extreme, triple-digit heat, begonias may pause their flower production to conserve energy. They will usually resume as soon as temperatures moderate. (longfield-gardens.com)

When to Water and Fertilize

Timing your care routine is just as important as timing your planting. Begonias have a specific preference for how they receive moisture and nutrients throughout the growing season. (longfield-gardens.com)

Watering by the "Top Inch" Rule

The best time to water begonias is when the top inch of soil feels dry to the touch. Because they grow from tubers (which act like water storage tanks), they are very sensitive to overwatering.

• Morning is Best: Watering in the morning allows any moisture on the leaves to dry before evening, which helps prevent mildew.
• Avoid the Center: Try to water the soil around the plant rather than pouring water directly into the center of the tuber "bowl," which can lead to rot. (longfield-gardens.com)

Feeding for Continuous Color

To keep the blooms coming all summer, you need to provide a steady supply of nutrients.

• Early Season: When the plant is just growing leaves, a balanced fertilizer is fine.
• Blooming Season: Once you see the first flower buds, switch to a fertilizer with a higher phosphorus count (the middle number on the fertilizer bag). This encourages more flowers rather than just more green leaves.
• Frequency: Every two weeks at half-strength is usually the "sweet spot" for container-grown begonias. (longfield-gardens.com)

What to Do Next: Summer Care

• Check soil moisture daily if your begonias are in small pots or hanging baskets.
• Remove spent blooms (deadheading) to keep the plant looking tidy.
• Apply a liquid fertilizer every 14 days to fuel new growth.
• Watch for "female" vs "male" flowers—tuberous begonias often produce a mix, and the male flowers are the large, showy ones!

When to Move or Store Begonias for Winter

As the season winds down, your begonias will begin to tell you when they are ready for a rest. Paying attention to these signals is the key to successfully overwintering your tubers so you can grow them again next year. (longfield-gardens.com)

Before the First Frost

The most critical timing rule for fall is this: do not let the tubers freeze. While a very light, "crunchy" frost might kill the leaves, a hard freeze that penetrates the soil will kill the tuber. If you live in a cold climate, plan to bring your containers onto a porch or into a garage as soon as night temperatures consistently dip into the 30s. (longfield-gardens.com)

Recognizing Dormancy

In late autumn, you will notice the leaves starting to turn yellow. This is not a sign of failure; it is the plant moving its energy from the foliage back down into the tuber for the winter. This is the "hibernation" phase.

• Stop Watering: Once the leaves begin to yellow, stop watering entirely. Let the soil dry out.
• The "Stem Drop": Eventually, the stems will become brittle and pull away from the tuber with a very gentle tug. If they don't come off easily, wait a few more days.

Digging and Curing

If your begonias are in the ground, dig them up after the first light frost has wilted the foliage.

1. Lifting: Carefully lift the tuber with a garden fork, being careful not to bruise it.
2. Curing: Lay the tubers out in a warm, dry, frost-free place (like a garage or basement) for about two weeks. This "cures" the outer skin and helps prevent rot during storage.
3. Storage: Once dry, remove any excess soil and store the tubers in a box filled with dry peat moss, perlite, or even shredded newspaper. Keep them in a cool, dark, dry place (around 50°F) until next spring. (longfield-gardens.com)

Key Takeaway: The end of the season is a transition, not an ending. By timing your harvest correctly, you turn your begonias into a multi-year investment. (longfield-gardens.com)

Troubleshooting Common Timing Issues

Sometimes, despite our best efforts, the timing feels "off." Here is how to handle the most common scenarios using simple, practical steps.

"My Begonias Aren't Sprouting"

If it has been four weeks and you see no green, the most likely cause is temperature. Begonias are sleepy! If your indoor starting area is below 60°F, they may stay dormant much longer. Try moving the pots to a warmer spot, such as on top of a refrigerator or near a gentle heat vent. Avoid the temptation to overwater them while you wait; too much water on a dormant tuber is the leading cause of rot. (longfield-gardens.com)

"The Plants Are Leggy and Tall"

If your begonias are growing very tall and thin early in the spring, they are likely searching for more light. This often happens when begonias are started indoors too early or kept in a window that is too dim. To fix this, move them to a brighter location or use a simple grow light. You can also "pinch back" the growing tips once the plant has a few sets of leaves to encourage a bushier, more compact shape. (longfield-gardens.com)

"Flowers Are Dropping Early"

If your begonia is dropping its flower buds before they even open, it is usually a reaction to a sudden change. This can be caused by a spike in extreme heat, a sudden drying out of the soil, or moving the plant from a very shady spot to a very bright one too quickly. Check your watering schedule and ensure the plant isn't getting hit by harsh, direct afternoon sun. (longfield-gardens.com)

"The Foliage Looks White and Dusty"

This is often powdery mildew, which tends to show up in late summer when the air is humid and the nights get cooler. To prevent this, focus on timing your watering for the morning and ensuring there is plenty of space between your plants for air to circulate. If it does appear, remove the most affected leaves and ensure the plant isn't sitting in a "dead air" corner of the porch. (longfield-gardens.com)

Selecting the Right Varieties for Your Timeline

When you choose which begonias to grow, think about where they will live and how you want them to perform throughout the season. Longfield Gardens offers a variety of shapes and sizes to fit different garden goals. (longfield-gardens.com)

For Maximum Impact: Tuberous Upright

If you want massive flowers that rival roses or camellias, look for upright tuberous varieties. These are fantastic for planting in the ground in shaded borders or in large patio pots. Because the flowers are so large, these varieties benefit most from an early start indoors to ensure they have the structural strength to hold up those heavy blooms by mid-summer. (longfield-gardens.com)

For Vertical Beauty: Hanging Basket Begonias

Cascading or trailing begonias are bred to spill over the edges of containers. They often produce hundreds of smaller blooms rather than a few giant ones. These are perfect for hanging baskets on a porch. Because hanging baskets dry out faster and are more exposed to the air, these are the ones you'll need to watch most closely for those late-spring temperature dips. (longfield-gardens.com)

For Low-Maintenance Color: Wax Begonias

If you don't want to worry about starting tubers indoors or storing them in the winter, wax begonias are an excellent "set it and forget it" option. They are very reliable and will bloom from the moment you plant them in May until the frost takes them in October. While they don't have the "wow" factor of the giant tuberous blooms, their consistency is unmatched. (longfield-gardens.com)

Conclusion

Growing begonias is a rewarding journey that adds incredible color to the quiet, shady parts of your landscape. By mastering the timeline—starting tubers indoors in late winter, waiting for the warm soil of late spring, and providing consistent care through the peak of summer—you can enjoy a professional-looking garden with very little stress. Gardening should be a source of joy, and few plants offer as much "bang for your buck" as a well-timed begonia. (longfield-gardens.com)

At Longfield Gardens, we are here to support you every step of the way with quality tubers and the practical advice you need to succeed. Whether you are a first-time gardener or a seasoned pro, the simple rules of warmth, patience, and consistent moisture will lead to a stunning display. (longfield-gardens.com)

• Start tubers 8-12 weeks before the last frost for an early bloom.
• Wait for 60°F soil and warm nights before moving plants outdoors.
• Fertilize every two weeks once blooms appear to keep the show going.
• Lift and store tubers in the fall after the foliage begins to yellow.

"The secret to beautiful begonias isn't a hidden trick—it's simply respecting their love for tropical warmth and giving them the time they need to shine."

Ready to start your shade garden transformation? We invite you to explore our selection of premium begonia tubers and start planning your most colorful summer yet!

FAQ

When is the best time to plant begonia tubers outdoors?

The best time to plant begonias outdoors is in late spring, once all danger of frost has passed and the soil has warmed to at least 60°F. In most regions, this happens in late May or early June. Planting too early in cold, wet soil can cause the tubers to rot or stunt their growth for the rest of the season. (longfield-gardens.com)

How early should I start my begonias indoors?

We recommend starting begonia tubers indoors about 8 to 12 weeks before your area's average last frost date. This usually falls in February or March for most US gardeners. Starting them early in a warm, bright indoor spot allows the plants to develop a strong root system and foliage, which leads to much earlier summer flowers. (longfield-gardens.com)

Can begonias survive the winter outside?

Begonias are only hardy in USDA zones 8-11, where the ground does not freeze. In zones 3-7, they are tender perennials and must be brought indoors or have their tubers dug up and stored in a cool, dry place for the winter. They are very sensitive to cold, so they should be moved to a protected area before the first hard frost of autumn. (longfield-gardens.com)

When do begonias usually start blooming?

If started indoors during the late winter, begonias often begin blooming in June. If planted directly outdoors in the spring, they typically start their main flowering show in July. Once they begin, begonias are "ever-blooming," meaning they will continue to produce flowers consistently until the first frost in autumn. (longfield-gardens.com)