Introduction
The sight of lush, velvet-textured begonias spilling over the edges of a hanging basket is one of the true joys of a summer garden. These tropical beauties are famous for their vibrant colors and ability to brighten up shady corners where other flowers might struggle. Whether you are looking for massive rose-like blooms or a delicate cascade of bell-shaped flowers, begonias are a rewarding choice for any skill level. If you are filling several baskets, the Non Stop Begonias collection is a useful bulk option. At Longfield Gardens, we enjoy helping gardeners transform their porches and patios with these spectacular, long-blooming tubers. For shopping, start with our Hanging Begonias collection.
This guide is designed to help you get the best results from your planting efforts, specifically focusing on the needs of hanging displays. We will cover exactly how deep to plant your tubers, which direction they should face, and how to care for them so they thrive until the first frost. If you prefer a quick-start example, Begonia Hanging Golden Balcony is a strong cascading variety. By following a few simple steps, you can create professional-looking baskets that bloom continuously all season long.
The secret to a successful begonia display starts with the very first step: getting the tuber into the soil at the correct depth and orientation. For a broader overview of begonia types and care, see Longfield Gardens’ All About Begonias guide.
The Short Answer: How Deep to Plant Your Tubers
When you are ready to plant your tuberous begonias in a hanging basket, the depth is the most important factor to get right. You should plant begonia tubers approximately 1 inch deep. This means that after you place the tuber on the soil, you should cover the top with about 1 inch of potting mix.
If you plant them too deep, the sprouts may struggle to reach the surface, and the tuber is more likely to rot in the damp soil. If you plant them too shallowly, the developing roots may dry out, or the plant might not have enough stability as it grows larger and heavier. A depth of 1 inch provides the perfect balance of protection and accessibility for the emerging stems.
Key Takeaway: For hanging baskets, cover your begonia tubers with exactly 1 inch of high-quality potting mix to ensure healthy growth and steady moisture levels.
Understanding the Begonia Tuber
Before you start digging, it helps to understand what you are working with. A begonia tuber looks like a small, brown, slightly hairy disk or bowl. Unlike a tulip bulb, which has a clear "pointy end" that goes up, a begonia tuber is a bit more subtle.
Identifying the Top and Bottom
Take a close look at the tuber. One side will be slightly indented or hollowed out, resembling a shallow bowl. This is the top of the tuber. This hollow area is where the growth buds—often called "eyes"—will emerge. The other side is rounded and smoother; this is the bottom, where the roots will eventually form.
Always plant the tuber with the hollow, "bowl" side facing up. If you accidentally plant it upside down, the sprouts will have to grow around the tuber to find the light, which wastes energy and delays blooming. If you aren't sure which side is which, look for tiny pink or red bumps in the hollow area. These are the "pips" or sprouts starting to wake up.
Why Quality Matters
The energy for those first several weeks of growth is all stored right inside that tuber. A firm, healthy tuber is packed with the nutrients the plant needs to kickstart its season. We work with experienced growers to ensure you receive tubers that are ready to perform. Starting with high-quality stock is the easiest way to ensure your hanging baskets look full and lush by midsummer.
Preparing Your Hanging Baskets
Hanging baskets are a unique growing environment. Because they are suspended in the air, they are exposed to more wind and can dry out faster than plants in the ground. Preparing the container correctly is just as important as the planting depth itself.
Choosing the Right Potting Mix
Never use garden soil in a hanging basket. It is too heavy and does not provide enough "drainage," which is simply the speed at which water leaves the soil. Begonias hate sitting in soggy soil, which can lead to tuber rot.
Instead, use a high-quality, peat-based potting mix. Look for a mix that is labeled for containers or hanging baskets. These blends are lightweight and often include perlite or vermiculite, which are the small white or silver flecks that help keep the soil airy and well-drained. You may also want to look for a mix that contains a "wetting agent" to help the soil absorb water more evenly.
Selecting the Basket Type
There are two main types of baskets for begonias:
- Plastic or Ceramic Pots: These hold moisture longer, which can be helpful during hot summer spells. Ensure they have adequate drainage holes at the bottom.
- Wire Baskets with Liners: These are classic and allow for a beautiful "overflowing" look. You will need a cocoa fiber or moss liner to hold the soil in place. Note that these baskets dry out very quickly, so they may require more frequent watering. A cascading variety like Begonia Hanging Pink Balcony works especially well here.
How Many Tubers Per Basket?
To get a full, professional look, you want to use the right number of tubers. If you are planting a larger display, the Begonia Upright Double Superba Mix - Bulk Offer gives you a generous 10 tubers to work with.
- 10-inch basket: Use 3 tubers.
- 12-inch basket: Use 4 to 5 tubers.
- 14-inch basket: Use 5 to 6 tubers.
Space the tubers evenly around the basket, about 3 to 5 inches apart. If you are using a cascading variety, place one tuber in the very center and the others in a circle around it. This ensures the flowers drape over every side of the pot.
Step-by-Step Planting Guide
Ready to plant? Follow these steps to ensure your begonias get the best start possible.
- Fill the Basket: Fill your hanging basket with moist potting mix until it is about 2 inches below the rim. Press the soil down gently to remove large air pockets, but do not pack it tight.
- Position the Tubers: Place your tubers on the soil surface with the hollow side facing up. Space them evenly according to the size of your basket.
- Cover with Soil: Add more potting mix over the tubers until they are covered by 1 inch of soil. The final soil level should be about 1 inch below the rim of the basket. This gap is important because it leaves room for water to pool and soak in rather than running off the sides.
- Water Gently: Use a watering can with a "rose" (a shower-head attachment) to water the basket gently. You want to settle the soil around the tubers without washing the soil away or displacing the tubers.
- Place in a Warm Spot: If it is still early in the season, keep the basket in a warm, bright indoor spot until the danger of frost has passed.
What to do next:
- Check the "bowl" side for sprouts before planting.
- Ensure your potting mix is pre-moistened.
- Leave a 1-inch gap at the top of the basket for easy watering.
- Label your baskets if you are growing different colors.
The Benefits of Pre-Sprouting
While you can plant dormant tubers directly into your baskets in late spring, many gardeners prefer to "pre-sprout" them. This gives the plants an 8-week head start, which means you will see flowers much earlier in the summer. For step-by-step timing, see How to Start Tuberous Begonias Indoors.
To pre-sprout, place your tubers in a shallow tray filled with moist potting mix or peat moss about two months before your last expected frost date. Keep the tray in a warm room (about 70°F) with indirect light. Once the sprouts are an inch or two tall and have a few leaves, you can carefully transplant them into your hanging baskets at the same 1-inch depth.
This extra step is particularly rewarding in northern climates with shorter growing seasons. It ensures that by the time the weather is warm enough for the baskets to go outside, they are already established and ready to bloom.
Light and Temperature Requirements
Tuberous begonias are tropical plants. They love warmth and humidity, but they are very sensitive to direct, hot sunlight and freezing temperatures.
Finding the Right Light
The ideal light for begonias is "filtered shade." This is the kind of light you find under a tall tree or a porch roof. They enjoy about 4 hours of morning sun, which is gentle and cool. However, they should be protected from the harsh, direct sun of midday and afternoon. If the leaves look scorched or the edges turn brown and crispy, the plant is likely getting too much sun.
Managing Temperature
Do not move your hanging baskets outside until the nighttime temperatures are consistently above 50°F. If a surprise late-spring frost is predicted, bring your baskets back into the garage or house for the night. If you are not sure how your climate compares, Longfield Gardens’ Hardiness Zone Map can help.
Watering Your Hanging Baskets
Watering is the most frequent task you will face with hanging baskets. Because the baskets are elevated, they lose moisture through the bottom and sides as well as the top.
The Finger Test
The best way to tell if your begonias need water is the "finger test." Stick your finger into the soil up to the first knuckle. If the soil feels dry, it is time to water. If it feels cool and damp, wait another day.
How to Water
When you water, do it thoroughly. Pour water onto the soil until it begins to run out of the drainage holes at the bottom. This ensures the entire root ball is saturated. Try to water the soil directly rather than pouring water over the leaves and flowers. Wet foliage can sometimes lead to mildew or spotting, especially in humid weather.
During the heat of midsummer, you may need to water your hanging baskets every single day. In cooler spring or fall weather, every few days might be enough.
Feeding for Continuous Blooms
Tuberous begonias are heavy feeders. They put a lot of energy into producing those large, showy flowers, and the limited amount of soil in a hanging basket can run out of nutrients quickly.
Choosing a Fertilizer
To keep the blooms coming, use a water-soluble fertilizer. A "balanced" fertilizer (like a 20-20-20 mix) works well for general growth. If you want to specifically encourage more flowers, you can switch to a "bloom booster" formula with a higher middle number (phosphorus) once the plant is well-established. For more begonia care basics, see Tips for Growing Tuberous Begonias.
Feeding Schedule
For the best results, fertilize your begonias every two weeks. Always apply fertilizer to moist soil—never fertilize a wilted or bone-dry plant, as the concentrated salts can burn the tender roots. If you prefer a "low-maintenance" approach, you can mix slow-release fertilizer granules into the potting mix at the time of planting, though supplemental liquid feeding usually yields more impressive results.
Maintaining Your Display
A little bit of grooming goes a long way in keeping your hanging baskets looking their best throughout the summer.
Deadheading
"Deadheading" is the process of removing faded or spent flowers. When a bloom starts to wilt, pinch off the flower head and the small stem attached to it. This prevents the plant from putting energy into seed production and encourages it to create more flower buds instead.
Protecting from Wind
Hanging baskets can act like sails in a storm. Begonias have relatively brittle stems that can snap in high winds. If a big storm is rolling through, it is a good idea to take your baskets down and place them in a sheltered spot on the ground until the wind dies down.
Supporting Upright Varieties
While cascading (pendula) begonias are the most common choice for baskets, some gardeners plant upright varieties for a different look. If you choose an upright type, the stems may eventually become top-heavy from the weight of the large blooms. You can use small bamboo stakes and soft garden ties to provide a bit of extra support. For that plant style, browse Upright Double Begonias.
End of Season Care
Tuberous begonias are not hardy in most of the United States, but you don't have to lose them when winter arrives. Longfield Gardens stands behind its plants with a 100% Quality Guarantee, so you can plant with confidence and enjoy the season.
In the fall, when the leaves start to yellow or after the first light frost, stop watering the basket. Allow the foliage to die back naturally. Once the stems are dry, they should pull away from the tuber easily. Dig the tubers out of the soil, gently brush off the excess dirt, and let them dry in a cool, dark place for a few days.
Store the dry tubers in a box filled with peat moss or vermiculite in a frost-free area (like a basement) where temperatures stay around 45–50°F. Next spring, you can start the process all over again.
Conclusion
Planting tuberous begonias in hanging baskets is a simple way to bring high-impact color to your outdoor living spaces. By remembering the "1-inch rule" for planting depth and ensuring the hollow side of the tuber faces upward, you have already conquered the most important part of the process. With consistent water, a bit of shade, and regular feeding, your begonias will reward you with a spectacular display of flowers that lasts from midsummer all the way to the first frost of autumn. If you are planning next spring's order, Longfield Gardens’ Shipping Information page explains when orders leave the warehouse.
At Longfield Gardens, we believe that gardening should be a rewarding experience for everyone, and begonias are the perfect plant to prove it.
Final Checklist for Success:
- Plant tubers 1 inch deep in a high-quality potting mix.
- Ensure the hollow "bowl" side faces the sky.
- Wait for nighttime temperatures to reach 50°F before moving baskets outside.
- Water whenever the top inch of soil feels dry to the touch.
FAQ
What happens if I plant my begonia tuber upside down?
If a tuber is planted upside down, the sprouts will still attempt to grow toward the light, but they will have to grow around the body of the tuber to reach the surface. This delays the emergence of the plant and uses up significant energy stores. If you realize you’ve made a mistake early on, you can gently dig it up and flip it over; otherwise, the plant will usually correct itself, though it will bloom later than usual.
Can I use regular garden soil in my hanging baskets?
It is not recommended to use garden soil in hanging baskets because it is too dense and heavy. Garden soil lacks the aeration needed for container plants and can easily become compacted, which prevents water from draining and causes roots to suffocate. Always use a lightweight, peat-based potting mix designed specifically for containers to ensure your begonias have the air and moisture balance they need.
Why are the leaves on my begonia turning brown at the edges?
Brown, crispy edges on begonia leaves are usually a sign of "sunscald" or heat stress. This happens when the plant is exposed to too much direct, intense sunlight, especially during the middle of the day. To fix this, move your hanging basket to a more shaded location that receives only gentle morning sun or dappled light throughout the day.
Do I need to soak begonia tubers before planting them in a basket?
While some gardeners like to soak tubers for an hour or two to "wake them up," it is generally not necessary if you are planting them into moist potting mix. The most important factor for starting the tubers is warmth and consistent (but not soggy) moisture. If you choose to pre-sprout them indoors, the humidity of the soil will naturally encourage the growth buds to emerge within a few weeks. If you want help choosing your planting window, see When to Plant Begonias Outdoors: Timing for Best Results.
