Begonias are popular garden plants because they bring bright flowers and attractive foliage to patios, flower beds, containers, and shady corners. However, choosing the right planting time is important if you want healthy growth and plenty of blooms throughout the season.
Unlike some hardy perennials, many begonias are sensitive to cold temperatures. Planting them too early can slow their growth or damage young plants, while waiting until conditions are warm enough gives them a much better start.
The best time to plant begonias depends on your climate, the type of begonia you are growing, and whether you are starting from seeds, tubers, or nursery plants.
For more information about growing requirements, varieties, and general growing tips, see our complete guide to Begonia.
When Is the Best Time to Plant Begonias?
For most gardeners, the safest time to plant begonias outdoors is after the danger of frost has passed and nighttime temperatures remain consistently above about 50°F.
Begonias prefer warm soil and mild temperatures. Cold, wet soil can cause slow growth and may increase the risk of root problems.
In areas with cold winters, gardeners usually start begonias indoors several weeks before the last expected frost. Once temperatures warm up, the young plants can gradually be moved outside.
If you live in a warm climate where freezing temperatures are uncommon, begonias may be planted outdoors much earlier and can sometimes grow nearly year-round.
Planting Begonias in Spring
Spring is generally the best planting season for begonias in much of the United States.
Wait until the soil has warmed and the risk of frost has passed. A warm spring gives begonias enough time to establish their roots before the hottest part of summer arrives.
For nursery-grown begonias, planting in late spring is often an easy option. The plants already have a developed root system, so they can settle into the garden relatively quickly.
Before planting, choose a location with good drainage and protection from intense afternoon sunlight. Many begonias grow especially well in partial shade.
If spring weather is still unpredictable, keep newly purchased begonias protected until temperatures become more stable.
When to Start Begonias From Seeds
Starting begonias from seed requires more patience because the plants need time to develop before they are ready for outdoor planting.
Begonia seeds are extremely small, and young seedlings can be delicate. In colder climates, gardeners often start seeds indoors approximately 10 to 12 weeks before the last expected spring frost.
Use a clean seed-starting mix and provide bright light. Keep the growing medium evenly moist without making it soggy.
Because seedlings develop slowly at first, starting early gives them enough time to become stronger before being transplanted outdoors.
Once the seedlings have several healthy leaves and outdoor conditions are warm enough, they can gradually be acclimated to outdoor conditions.
When to Plant Begonia Tubers
Tuberous begonias follow a slightly different schedule. Their underground tubers can be started indoors before the outdoor growing season begins.
Gardeners in cooler climates often start tubers indoors in late winter or early spring. Place the tubers in a shallow container with a well-draining growing medium, keeping the growing environment warm and bright.
Once the plants begin producing healthy shoots and outdoor temperatures are consistently mild, they can be transplanted outside.
Avoid putting tubers directly into cold, waterlogged soil. Warm conditions are much more favorable for new root and shoot development.
Choosing the Right Planting Time by Climate
Your local climate is more important than the calendar when deciding when to plant begonias.
In northern states, where spring frosts can continue into May, begonias are usually planted outdoors later in the spring.
In the Midwest and parts of the Northeast, late May or early June may be appropriate depending on the local weather.
In southern states, warm temperatures arrive earlier. Gardeners may be able to plant begonias outdoors during early or mid-spring.
In warm regions such as Florida and parts of the Gulf Coast, begonias can often be grown for much longer periods of the year.
Rather than following a specific date, pay attention to soil temperature, nighttime temperatures, and your local frost forecast.
Where to Plant Begonias
Choosing the right location is just as important as choosing the right planting time.
Most begonias appreciate bright, indirect light or partial shade. Some varieties can tolerate more sunlight, especially when they receive adequate moisture, but harsh afternoon sun can cause leaf damage in sensitive types.
A location with morning sun and afternoon shade is often a good choice.
Good drainage is also essential. Begonias enjoy consistent moisture, but their roots should not remain in standing water.
Before planting, improve heavy soil with organic matter if necessary. Container-grown begonias should be planted in pots with drainage holes.
For more information about growing requirements, varieties, and general growing tips, see our complete guide to Begonia.
How to Prepare Begonias for Outdoor Planting
If you started begonias indoors, do not immediately move them from a protected indoor environment into full outdoor conditions.
Instead, gradually introduce them to outdoor weather. This process is commonly called hardening off.
Start by placing the plants outdoors for a short period in a sheltered location. Gradually increase the amount of outdoor time over approximately one to two weeks.
Avoid exposing young plants to strong wind, cold nights, or intense afternoon sunlight during the first few days.
Gradual acclimation reduces transplant stress and helps begonias adjust to their new environment.
The Best Time to Plant Begonias in Containers
Begonias are excellent container plants, and containers give gardeners more control over growing conditions.
Because containers can be moved indoors or into a sheltered location, you can sometimes plant begonias slightly earlier than you would plant them directly in the garden.
However, cold temperatures can still damage the plants.
Choose a container with drainage holes and use a lightweight potting mix. Avoid placing the container in a location where rainwater consistently collects.
Containers also tend to dry out faster than garden soil, so check the moisture level regularly during warm weather.
What Happens If You Plant Begonias Too Early?
Planting begonias too early is one of the most common mistakes gardeners make.
Cold soil can slow root development, while chilly nights may cause plants to stop growing normally. A late frost can be especially damaging to young plants.
Even if the weather feels warm during the day, nighttime temperatures can remain too low for tender begonias.
If an unexpected cold spell is forecast, container-grown plants can be moved to a protected location. Garden plants may need temporary protection from cold weather.
Waiting a little longer is usually better than rushing begonias into the garden.
What If You Plant Begonias Too Late?
Planting later than ideal is generally less serious than planting too early.
Begonias can still establish themselves during warm weather as long as they receive suitable light, moisture, and soil conditions.
However, very late planting may give the plants less time to develop before extreme summer heat or the end of the growing season.
If you purchase mature nursery plants later in the season, choose healthy specimens and keep them consistently watered while they establish their roots.
Final Thoughts
The best time to plant begonias is when the weather has become reliably warm and the danger of frost has passed. In cooler climates, starting seeds or tubers indoors can give plants a valuable head start.
For outdoor planting, focus less on a specific calendar date and more on local conditions. Warm soil, mild nights, good drainage, and appropriate light will give begonias the strongest beginning.
With the right timing and a suitable growing location, begonias can reward you with colorful flowers and attractive foliage throughout the growing season.