Table of Contents
- Introduction
- Why Proper Spacing Matters for Begonias
- Spacing for Wax Begonias
- Spacing for Tuberous Begonias
- Special Spacing for Large Varieties
- Calculating How Many Plants You Need
- Best Soil and Site Conditions
- Planting Depth and Technique
- Timing Your Planting
- Designing with Spaced Begonias
- Watering Your New Plants
- Maintenance and Long-Term Care
- Managing Pests and Diseases
- Overwintering Your Begonias
- Creating a Seamless Look
- Regional Considerations for Spacing
- Conclusion
- FAQ
Introduction
Walking into a garden filled with the lush foliage and brilliant blooms of begonias is one of the true joys of summer. These versatile plants are a favorite for adding reliable color to those tricky, shaded corners where other flowers might struggle. Whether you are looking for the delicate, waxy leaves of bedding begonias or the massive, rose-like blooms of tuberous varieties, getting your garden layout right starts with one simple question.
Knowing how far apart to plant begonias in the ground is the secret to a professional-looking landscape. At Longfield Gardens, we want to help you create a display that looks full and vibrant without overcrowding your plants, and our Begonia Flower Bulbs for Sale collection is a great place to start. Proper spacing ensures each begonia has the room it needs to breathe, grow, and produce those stunning flowers all season long.
In this guide, we will walk through the specific spacing requirements for different begonia types and share tips for preparing your soil. For a broader overview, see our All About Begonias guide.
Why Proper Spacing Matters for Begonias
When you first bring home young plants or unsprouted tubers, they look small and unassuming. It is tempting to plant them very close together to make the garden bed look full immediately. However, giving your begonias enough elbow room is one of the best things you can do for their long-term health.
Begonias are tropical plants that thrive in humid environments, but they also need good air circulation. When plants are packed too tightly, air cannot move between the leaves. This creates a stagnant environment where moisture sits on the foliage for too long. Proper spacing helps the leaves dry out after a rain or watering session, which keeps the plants looking fresh and vibrant.
Allowing for enough space also ensures that each plant has its own "pantry" of nutrients and water. If begonias are crowded, they have to compete for the resources in the soil. This can lead to smaller flowers and slower growth. By following recommended spacing guidelines, you give each plant the best chance to reach its full potential.
Key Takeaway: Correct spacing promotes healthy air circulation and reduces competition for soil nutrients, leading to larger blooms and stronger plants.
Spacing for Wax Begonias
Wax begonias, also known as bedding begonias, are the classic choice for creating ribbons of color along walkways or mass plantings in garden beds. These plants are generally smaller and more compact than their tuberous cousins. Because they stay relatively tidy, you can plant them closer together than other varieties.
For a standard garden bed, space wax begonias 6 to 10 inches apart. If you want a dense "carpet" of color where the plants eventually touch and hide the soil, aim for the 6-inch mark. This is a popular choice for public gardens and formal borders. If you prefer to see the individual shape of each plant, 10 inches is a better choice.
Wax begonias usually grow to be about 6 to 12 inches tall and wide. They have a mounding habit, which means they grow outward in a soft, rounded shape. When you space them at 8 inches, they will typically fill in the gaps within a few weeks of planting. This creates a lush, seamless look that is very effective at suppressing weeds.
What to do next:
- Measure your garden bed to calculate how many plants you need.
- Use a measuring tape or a pre-marked stick to keep your spacing consistent.
- Place the potted plants on the soil surface before digging to visualize the final look.
Spacing for Tuberous Begonias
Tuberous begonias are the "showstoppers" of the shade garden. They produce much larger flowers, often reaching 4 to 8 inches across, and they have broader, more dramatic foliage. Because these plants grow larger and have a more open structure, they require more room than wax begonias.
Varieties like the Non-Stop Begonias series have a vigorous growth habit.
The stunning Begonia Upright Double Picotee White is another good example. Giving them a full foot of space ensures the heavy blooms have enough support from the surrounding stems.
Some upright tuberous varieties can reach heights of 12 to 18 inches. If you are planting in a very sheltered area with little wind, you can stick to the 10-inch spacing. In areas where you want maximum airflow to keep the foliage cool, 12 inches is the gold standard. This spacing also makes it easier to reach into the bed for light maintenance or to admire the flowers up close.
Special Spacing for Large Varieties
While most begonias fit into the standard 6-to-12-inch window, some specialty varieties need even more room. If you are planting "Dinnerplate" begonias or large-scale varieties like Begonia Double Maxima Switzerland, you should consider increasing your spacing to 15 or even 18 inches.
These larger plants are bred for their massive size and dramatic impact. Switzerland begonias, for example, feature dark, chocolatey-bronze foliage that provides a stunning contrast to their bright red flowers. To truly appreciate the color of the leaves and the architectural shape of the plant, you don't want them crushed against their neighbors.
When working with these larger types, think of them as individual garden features rather than just a groundcover. Spacing them further apart allows each plant to become a focal point. This is especially effective when you are mixing begonias with other shade-loving perennials.
Key Takeaway: Always check the specific variety of begonia you are planting, as large-flowered types like Dinnerplate varieties need up to 15-18 inches of space.
Calculating How Many Plants You Need
Before you start digging, it helps to do a little bit of garden math. Knowing your spacing allows you to buy exactly the right number of tubers or plants from us at Longfield Gardens. This prevents the frustration of having extra plants with no home or a half-empty garden bed.
To calculate the number of begonias needed for a rectangular bed, multiply the length of the bed by the width to get the square footage. Then, use these general rules of thumb:
- For 6-inch spacing: 4 plants per square foot.
- For 8-inch spacing: 2.25 plants per square foot.
- For 10-inch spacing: 1.5 plants per square foot.
- For 12-inch spacing: 1 plant per square foot.
If your garden bed is irregularly shaped, you can use a "staggered" or "triangular" planting pattern. Instead of planting in straight rows like a grid, offset every other row. This helps the plants fill in the gaps more naturally and makes the bed look fuller with slightly fewer plants.
Best Soil and Site Conditions
The distance between your plants is only one part of the success equation. Where you put them is just as important. Begonias are famous for their love of shade, but "shade" can mean many things. Most begonias do best in filtered light or a spot that gets morning sun and afternoon shade, as explained in our Where to Plant Begonias: Sun or Shade? Expert Guide.
The soil should be the star of your site preparation. Begonias have relatively shallow, delicate root systems. They prefer soil that is rich in organic matter and very well-drained. "Well-drained" simply means that water moves through the soil easily and does not leave the roots sitting in a puddle.
If your garden has heavy clay soil, the water might move too slowly. You can improve this by mixing in some compost or finely shredded bark before you plant. This creates tiny air pockets in the soil, which begonias love. For the best results, aim for soil that feels like a wrung-out sponge—moist but not dripping wet.
What to do next:
- Check your chosen spot after a rain to see if water puddles.
- Add a 2-inch layer of compost to the surface and move it into the top 6 inches of soil.
- Ensure the area is protected from strong, drying winds.
Planting Depth and Technique
Once you have determined your spacing, it is time to get the plants into the ground. If you are starting with tubers, the depth is just as important as the distance. For more details, see our How Deep Should Begonias Be Planted for Success? guide.
Dig a small hole and place the tuber about 1 inch below the soil surface. You do not need to bury it deep. In fact, many gardeners prefer to just barely cover the top of the tuber with a thin layer of soil. This makes it easier for the tender sprouts to reach the light.
If you are transplanting begonias that are already growing in nursery pots, dig a hole that is twice as wide as the pot but no deeper. When you place the plant in the hole, the top of the root ball should be level with the surrounding garden soil. Gently firm the soil around the roots with your hands to remove any large air pockets.
Timing Your Planting
Begonias are true children of the tropics. They have no tolerance for frost, and they don't even like chilly nights. Even if the sun is shining, cold soil can cause begonias to sit and pout rather than grow. Patience is a virtue when it comes to planting these beauties, and our When Can You Plant Begonias Outside? guide can help you time it right.
Wait until the danger of frost has completely passed and the soil has warmed up to at least 60°F. In most parts of the United States, this is usually a few weeks after the local "last frost date." A good rule of thumb is to wait until you are comfortable wearing a light t-shirt outside at night.
If you live in a northern climate with a short growing season, you can start your tubers indoors in pots about 6 weeks before the last frost. For an early-start refresher, see How to Start Tuberous Begonias Indoors. This gives them a head start so they are already leafed out when it is finally warm enough to move them into the ground. This "jump start" ensures you get the maximum amount of bloom time during the summer months.
Key Takeaway: Never rush begonias into the ground; wait for consistent nighttime temperatures above 50-60°F to ensure the plants thrive.
Designing with Spaced Begonias
Proper spacing opens up wonderful design possibilities in the shade garden. Because you know how much room each plant will take up, you can plan companion plantings that complement the begonias without crowding them out.
One of the most classic combinations is planting begonias alongside hostas and ferns. Hostas provide broad, structural leaves in shades of green, blue, and gold. Ferns add a delicate, feathery texture. Because hostas can grow quite large, make sure to space your begonias at least 12 to 15 inches away from the center of a hosta plant to give both enough room to shine.
You can also use spacing to create color patterns. For a formal look, try planting rows of wax begonias in alternating colors—such as white and red. If you use 6-inch spacing, these rows will quickly grow together to create solid stripes of color. For a more cottage-garden feel, mix different colors of tuberous begonias and space them more widely (12 inches) to allow other low-growing plants like creeping jenny to fill the gaps.
Trailing begonias, like those in our Hanging Begonias collection, are often used in hanging baskets, but if you plant them in the ground as a groundcover, use the same 10-to-12-inch spacing.
Watering Your New Plants
After you have spaced and planted your begonias, they will need a good drink to settle into their new home. However, watering begonias requires a slightly different approach than other garden flowers. Because their stems and leaves are succulent (meaning they hold a lot of water), they can be prone to rot if kept too wet.
When you water, try to direct the stream at the base of the plant rather than over the top of the leaves. This keeps the foliage dry and reduces the chance of fungal issues. If you have spaced your plants correctly, the soil between them will have a chance to dry out slightly between waterings, which is exactly what begonias prefer.
A layer of mulch can be very helpful, but be careful not to pile it up against the stems of the plants. A thin, 1-inch layer of shredded bark or compost around the plants helps keep the soil moisture consistent. This is especially important for tuberous begonias, which like their "feet" to be cool and moist but never soggy.
What to do next:
- Water in the morning so any accidental splashes on the leaves can dry in the sun.
- Check the soil with your finger; if the top inch is dry, it is time to water.
- Avoid using a high-pressure nozzle that could break the brittle stems.
Maintenance and Long-Term Care
As the summer progresses, your well-spaced begonias will begin to fill their designated areas. One of the great things about begonias is that they are relatively low-maintenance. Most modern varieties are "self-cleaning," meaning the old flowers fall off on their own, so you don't have to spend hours deadheading.
If you notice that your wax begonias are starting to look a little "leggy" or stretched out, don't be afraid to give them a light trim. This encourages the plant to branch out and become bushier. Because you provided enough space at the start, the plant has the room to grow wider and more lush after a trim.
Fertilizing is also important for keeping the show going until frost. Use a balanced, water-soluble fertilizer every two to four weeks. Follow the instructions on the package for the correct dilution. Regular feeding ensures that the plants have the energy to keep producing those large, colorful blooms that made you fall in love with begonias in the first place.
Key Takeaway: Spaced plants are easier to fertilize and maintain, as you can clearly see the base of each plant and monitor its health throughout the season.
Managing Pests and Diseases
Even with perfect spacing and care, nature sometimes brings a few challenges. The good news is that spacing is your first line of defense against most begonia problems. By providing that essential air circulation, you are already preventing the most common issue: powdery mildew.
Powdery mildew looks like a light dusting of flour on the leaves. It usually happens when the air is humid and still. If you see this, you can treat it with a simple neem oil spray or a mixture of baking soda and water. Because your plants are spaced correctly, the treatment will be more effective because it can reach all parts of the foliage.
Slugs and snails also enjoy the cool, damp environment of a begonia bed. If you notice small holes in the leaves, you can use a pet-safe slug bait or even just hand-pick them in the evening. Keeping the soil surface clear of debris and ensuring your plants aren't overcrowded makes it much harder for these pests to hide.
Overwintering Your Begonias
As autumn approaches and the first frost threatens, you have a choice to make. In most parts of the country, begonias are grown as annuals, meaning they finish their life cycle when the cold hits. However, if you have grown tuberous begonias, you can save the tubers to plant again next year.
Once the foliage begins to yellow or after the first very light frost, carefully dig up the tubers. Shake off the excess soil and let them dry in a shady, frost-free spot for about a week. Once they are dry, you can cut off the remaining stems. Store the tubers in a cool, dark place (around 50°F) in a box filled with dry peat moss or shredded paper.
Wax begonias are a bit harder to save as tubers, but many gardeners like to take cuttings or bring the entire plant indoors to live as a houseplant during the winter. Simply pot them up and place them in a bright window. When spring returns, you can move them back outside, following the same spacing rules you used the year before.
Creating a Seamless Look
If you follow the 8-to-12-inch spacing rule, you might worry that your garden will look "patchy" for the first few weeks. This is a normal part of the gardening process! It takes a little time for the roots to establish and for the top growth to take off.
To bridge the gap, you can use temporary fillers. Planting a few clusters of low-growing annuals like lobelia or alyssum between your begonias can provide immediate color. These "filler" plants have very shallow roots and won't compete heavily with your begonias. As the begonias grow and claim their space, the fillers will naturally be covered or can be easily removed.
Another trick is to use mulch that matches the color of your soil. Dark brown or black mulch makes the vibrant green and red of the begonia foliage pop. It also creates a clean, unified background that makes the garden look finished from day one, even before the plants have filled in their assigned spaces.
Regional Considerations for Spacing
While the general rules for spacing apply to most gardens, your local climate can play a small role in your decision. Gardening is rarely a "one size fits all" activity, and observing your specific environment will help you make the best choice. If you are unsure, our Hardiness Zone Map can help you match plants to your climate.
In very hot, humid regions like the Southeast, air circulation is even more critical. If you live in an area where the air feels heavy and damp all summer, lean toward the wider end of the spacing spectrum. Giving your tuberous begonias 14 inches instead of 12 can make a big difference in preventing fungal issues during a long, muggy summer.
In cooler, northern climates with shorter summers, you might want to space your plants slightly closer together. Since the plants have a shorter window to grow, they might not reach their maximum width before the first frost. Using 10-inch spacing for tuberous types in the North can help you achieve that "full" look a bit faster.
Conclusion
Mastering the art of how far apart to plant begonias in the ground is a simple step that yields huge rewards. By giving your wax begonias 6 to 10 inches and your tuberous varieties 10 to 12 inches of room, you are setting the stage for a healthy, vibrant, and disease-resistant garden. These spacing choices allow each plant to flourish, creating a professional-looking display that will be the envy of the neighborhood.
At Longfield Gardens, we believe that gardening should be a rewarding and enjoyable experience for everyone. Whether you are filling a massive border or just tucking a few tubers into a small shade bed, these basics will ensure your success. Remember to wait for warm weather, prep your soil with a bit of compost, and respect the space each plant needs to grow.
- Wax Begonias: 6–10 inches apart for a dense or individual look.
- Tuberous Begonias: 10–12 inches apart for airflow and bloom support.
- Large Varieties: 15–18 inches apart to showcase dramatic foliage.
- Wait for Warmth: Ensure night temperatures are consistently above 50-60°F.
"A beautiful garden is built on a foundation of simple, healthy choices. Giving your begonias the right amount of space is the first step toward a summer full of spectacular color."
We look forward to helping you grow your best garden yet. Start planning your shaded sanctuary today, and enjoy the nonstop beauty that only begonias can provide.
FAQ
Can I plant begonias closer together if I want a fuller look immediately?
While you can plant them slightly closer, such as 6 inches for wax begonias, it is important not to overcrowd them. Overcrowding limits airflow and can lead to issues like powdery mildew or stunted growth. Using the recommended spacing and a bit of patience will result in a much healthier and more beautiful garden by mid-summer.
Does spacing change if I am planting begonias in a container?
Yes, spacing in containers is typically tighter than in the ground. In a pot or window box, you can space tuberous begonias about 4 to 6 inches apart. This creates a lush, "overflowing" look that is desirable for containers. However, you will need to monitor the soil moisture more closely, as crowded pots dry out faster. For a more detailed walkthrough, see our How to Plant Tuberous Begonias in Pots guide.
Should I space trailing begonias differently than upright ones?
Trailing begonias are often used in hanging baskets, but if you plant them in the ground as a groundcover, use the same 10-to-12-inch spacing. Their stems will spread outward rather than upward, so they still need plenty of room to branch out without overlapping too densely, which helps keep the soil underneath from staying too wet.
How do I know if my begonias are planted too far apart?
If you can still see large patches of bare soil between your plants by mid-July, they may be spaced too far apart for your specific variety or climate. Next year, you can try reducing the distance by 2 inches. For this year, adding a nice layer of mulch or a few small filler plants can help the bed look more cohesive and finished.